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 Gift of Seymour B. Durst Old York Library 
 
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A 
 
 E E P O R T 
 
 '>X TIIK. 
 
 i;XTENT AND CHARACTER OF TIIK J)ISTI!ICT 
 SUPl'LYLNG AVATER 
 
 TO THK 
 
 CITY OF BIlOOKLY:Nr. 
 
 BV 
 
 THEODOEE AVESTON, C. E. 
 
 WITH A 
 
 COMMUNICATION IN RELATION TO THE SAME, 
 
 FKCI.M 
 
 JAMES P. IvlKKAVOOD, ESQ. 
 
 ENGINEER OF THE WORKS. 
 
 \M> AN' 
 
 ANALYSIS OF THE WATKil OF THK JAMAICA KFSERVOIU, 
 
 Hy Vkov. a K. KATUN, Cukmist. 
 
 li n ( » ( > K L Y N . N ^• 
 1801. 
 
D . VA N NOSTRA N D , 
 PUBLISHER. 
 
K E P O E T 
 
 ^roohlnn ^o;ub of (i'clliitcr (Tommissionci-s, 
 May 10th, 18G0. 
 
 A coMMTXTCATrox was received from the C'liief 
 Eiigineei', ^vitll a inaj) of tlie drainage area of tlie 
 streams fi'oiii Avliicli the su])])ly of the eity is now 
 arranged to he procured, together a\ ith t\vo slieets 
 of ])rofik^s^ showing certain characteristics of the 
 great water reservoir under the Hempstead Phiins, 
 and a i'e])ort from Mr. T. AVeston, explanatory of 
 this drainage ; also a re])ort from Professor A. K. 
 Eaton, shoAving a gradual inipi'ovenieiit of the cliai*- 
 actt'r of the water of Jamaica Pond duiiiiLi" tlic tiist 
 season, cVrc 
 
 Referred to Messrs. I>revoort and I^rn^li, w itli 
 the ])oW('i' to piint. 
 
6 
 
 EncxIxeer's Office, May 9fh, 1860. 
 
 WiLLiA:\r Wall, Esq., 
 
 Vice-President^ dr. 
 
 SiE : — I sul^mit lierewitli a map of tlie drainage 
 area or water-slied of tlie streams from wliicli tlie 
 supply of tlie city of Brooklyn is now arranged to 
 l)e procured, together witli profiles, showing certain 
 characteristics of the great water reservoir under 
 the Hempstead Plains, and an interesting report 
 from Mr. Weston, explanatory of this drainage. 
 
 In a note to my rej^ort on the gaugings of the 
 different supplying streams (Januar}^, 1 858), I esti- 
 mated, from th(* map of Long Island, the drainage 
 area referred to as comprising al)()ut thirty-four 
 square miles. 
 
 The old map of Long Island, from which I made 
 this measurement, was too general and indefinite in 
 its character to furnish correct results of this kind ; 
 I therefore directed Mr. Weston, last Fall, to take 
 advantage of the leisure which the stoppage of the 
 mason- work on the conduit presented, to obtain a 
 correct outline of the drainage-l)asin. To this he 
 applied the conduit parties in December last, and 
 the service has been j^erformed by all concerned 
 very satisfactorily. 
 
7 
 
 Instead of .'U s<[uar(' iiiiks of av.iilaldc waliT- 
 slu'd, as I lia'l sii])posc'(l lV<»iii the <>1<1 iii;i]>, tlir 
 correct survey sliows an aggregate of r.oj s(juai-c 
 miles connected \\itli tlie streams ai-c ii<»\v 
 
 ])re])arcd for use, and 1 :> s(|uare uiiles of una}>j»lied 
 drainage area, l>e](»nging to Springiield Pond, and 
 various small streams not availaMe foi* pondage. 
 
 Of tlie average annual rain-l'all lalling u[>on any 
 riverd)asin, a certain fraction finds its Avay int<> tlie 
 channel (►f the stream, either diicctly upon the sur- 
 face, or after ])ercolation through the earth and 
 strata underneath. Another fraction is consume(l 
 l)y evaporation and vegetation, and another fraction 
 finds its Avay to\vards the sea Ly underground crev- 
 ices and channels, and never escapes again to the 
 surface. 
 
 This last fraction must he more than usually 
 large on the TIem]>stead Plains hasin, \vliere the 
 natural formation ])resents no rocks or cla\' to inter- 
 cept the last-descrilxMl ])nrtion (►f tlie rain-fall and 
 force it to the surface, l»ut, on the contiary, presents 
 no oltstaele to il^ descent seaward on the spaces (»f 
 ground intervening hetwcen the various \ alleys, 
 e.\ce]>t the friction of the particles of sand, f )und in 
 this case to he e(jual to a late of descent ot* \'2 feet 
 to the mile. 
 
 Jt has long a])peare(l to me that much of this 
 
8 
 
 last portion of the reservoir water might he inter- 
 cepted hy underground drainage ; hut it might 
 require these drains to he j)laced so low as to involve 
 pum})ing to deliver the water into the conduit. 
 
 The AN^ater thus obtained is j^ure and limpid, and 
 entirely free from the discoloration which attends, 
 more or less, the water of the open streams. The 
 subject, at some future time, will merit a closer 
 study. 
 
 The water of some of the streams is sometimes 
 found to l)e slightly l)ro^\ n in color. The Jamaica 
 Pond A\'ater, Avlien first used, was at times consider- 
 ably tinted in this Ava} ; it is but little affected in 
 this Avay now, though the evil can never, in my 
 opinion, l)e entirely obviated luitil certain deposits 
 of muck above the pond are either partially 
 or A\liolly removed. The muck thrown out from 
 Jamaica Pond was, during the first season, covered 
 in spots with a Avliite efflorescence of a bitter taste ; * 
 and a similar salt was found deposited on the gravel 
 at the Avater s edge of the u])2)er end of the pond. 
 
 The pools of standing Avater outside of the pond, 
 lying in contact AN'ith the muck spoil banks, had the 
 same bitter taste. 
 
 I sent, at that time, specimens of the Avater of 
 the pond, draAvn from different points, and of these 
 pools, to Prof Eaton, chemist, for examination, 
 
9 
 
 and suldiiit licrcw itli liis i'('|M»rt t]i('ro(Hi. His report 
 is very satisfactory, as showing a gradual inij>r()V('- 
 nient in the eliaracter of tlie watei- of Jamaica 
 Pond during the first season, and a ])ro])a])ility that 
 the same de])tli of discoloration will not occur again. 
 
 To I'id all the streams of the impui'ities referre(1 
 to, and the tendenc\ to discoloration lirowini'' out of 
 the lai'ge de])osit of muck in tlieir channel-ways, 
 will he a work of considerahle time. 
 
 Within the limits of the diiferent su])ply reser- 
 voirs, the muck has heen entirely removed; hut, 
 al)<>ve the I'eservoirs, nothing has heen done as yet 
 to se|)arate the channels of the streams from the 
 vegetal )le accumulation through which they Wow. 
 
 At Jamaica J^)nd the discoloration can he 
 readily traced to the cause suggested. AVhen the 
 l)ond is draAvn down 1:2 or IS inclies, so that its 
 surface Avater does not correspond Avith the surface 
 of the hog or swamps ahove, the discoloration all 
 hut ceases ; for the ra])id floAV of the water tlirougli 
 a channel situated in the muck deposit seems to 
 affect it hut little, com]>ared with it^ sIonv ]>rogress 
 there an hen the surface of the A\ ater lies steeping 
 o\-er the surface of the hosr. 
 
 At Jamaica Pond, the I'emoval of the muck on 
 Rider's Creek \vould tend nuich to the improvement 
 of the water tliere ; and the excavation of a Avide 
 
10 
 
 channel-way in the main creek wouhl, it is thought, 
 be of service in the same way. Instead of removing 
 the muck where the deposit is Lai"ge, it may answer 
 the same purpose to cover its surface with two or 
 three feet of sand or gravel, enlarging, at the same 
 time, and straightening the channel of the stream. 
 
 This Avill prevent the water spreading over the 
 bottom as now, and confine it to the creek channel. 
 
 Jamaica Pond Avater appears to l)e more sub- 
 ject to discoloration than the water of the other 
 ponds, arising, probal>ly, from the fact that the 
 accumulation of vegetable matter in tlie valley of 
 this stream is nuich greater tlian in the valle}'s of 
 the other streams ; from which it may be inferred 
 that this stream Avas ponded and used long before 
 the other streams to the east of it. 
 
 The other j)onds show a l)etter color of water 
 than Jamaica, and ^vhen the ne^v conduit is fin- 
 ished, and their waters can l)e brought down, they 
 will prol)aT)ly modiiy^ and ini])rove nnich the tone of 
 the present Av^ater. 
 
 Some legislation seems necessary to give the 
 city the right hereafter to take such action in the 
 valleys of the streams as will secure at all times 
 pure water, whether b}' mucking out those valleys 
 gradually, or following tlie other course suggested 
 above. 
 
 JAMES P. KIRKWOOD. 
 
11 
 
 jA:\rEs P. KiijKWOOD, Esq., 
 
 DkaPv Sik : — At your i"e([iU'st 1 have nia<l»* a 
 full analysis of tlie Avater of Jamaica Pond, tlic 
 source of tlic })ivscnt 8Uj)})ly of water to tlic city of 
 P)i*o()lvlyn, and also ])artial analyses of tlic Avatcr of 
 Beaver Creek, wliicli flows into tliis ])ond, and of 
 that of some pools outside the ])ond, at ])oints 
 designated as stations 19 and 24 (see sketch). 
 
 The analysis of the water from the centre of the 
 pond gives the following results in grains per gal- 
 lon : — 
 
 
 .()1)7 
 .21 1 
 
 
 Sodium, .... 
 
 .078 
 
 Phospliatcs (iron and 
 
 
 
 .:U)9 
 
 Sulphuric Acid, , 
 
 .195 
 
 Chloi-iiio, 
 
 .li:i 
 
 Carbonic Acid, in oni- 
 
 
 
 .804 
 
 Silica, 
 
 .708 
 
 Organic flatter, 
 
 1 
 
 4.899 
 
 CoMniNED AS FOLLOWS : 
 
 Carl)<»natc of Lime, 998 
 
 Suljdiatc of Lime, 882 
 
 Chloride of Sodium,. . . .180 
 Carbonate of Magnesia, .577 
 Piinspliatcs : iron and 
 
 alumina 809 
 
 Silica, 703 
 
 Oi-ganic matter and 
 
 lns< l.-2;i4 
 
 4.899 
 
 Comj»ariiig tlie^e results with (dlicrs o]>tained 
 from examination <d' tlic water a^ taken from tlie 
 
12 
 
 pipes in Brooklyn May 18tli, 1859, and again from 
 tlie pond Sept. 1st, 1859, tliere appears to have heen 
 a decided improvement taking place in tlie quality 
 of tlie water up to tlie period when tlie sample was 
 taken, of wliicli tlie analysis is given above. This 
 was Dec. 23d, 1859. This is readily seen hy placing 
 the results together, as foUow^s : — 
 
 
 Water of 
 
 Water of 
 
 Water of 
 
 
 May ISth. 
 
 Sept. 1st. 
 
 Dec. 23d. 
 
 Organic matter, grains per gall., 
 
 8.285 
 
 1.852 
 
 1.234 
 
 Inorganic matter, " " 
 
 5.475 
 
 4.478 
 
 3.165 
 
 Solid residue, " " 
 
 8.760 
 
 6.330 
 
 4.399 
 
 The impurities in the water examined in May 
 were owing, no doul)t, in part to the accumulation 
 of foreign matters in tlie i)ipes previous to the 
 distril)ution of the water, as the pipes were then 
 just opened. The proportion of iron obtained in 
 December was much less than in either of the 
 preceding examinations, and this is a direct eifect 
 of the diminution of saline matters in tlie pond 
 water, the character and source of Avhich will l)e 
 noted below. 
 
 The next examination is of tlie water of Beaver 
 Creek, a swift-running stream, which is tlie chief 
 source of supply of the pond. This })roves to be a 
 
1 :\ 
 
 ])Uivi' water than tliat of tlic other sti'eaiiis, and 
 contains mneh less o\i(K' ot' iron and less of tlie 
 sulphates than the pond water. It gives, l)y 
 evaporation, — 
 
 ()i-g;iuie nijitter, in grains per ^i^alloii, 1,120 
 
 Inorganic matter, '* " 2.091 
 
 Solid residue, " " 4.111 
 
 In the inorganic matter I detected cldoride of 
 calcium, the presence of which accounts for a 
 remarkal)le cloudiness that is produced as the 
 waters of the l)rook meet those of the pond. For 
 the latter, containing soluhle sulphate of iron and 
 alumina, a double dec()mj)()sitioii takes place, and a 
 cloudy ])reci])itate of sul})hate of lime is produced, 
 which is distinctly perceptiMe in the large Lulk of 
 water, though not noticeable when the experiment 
 of mixing is tried in small portions. 
 
 Along the margin of the 2>oii<l on the east side, 
 
 and separated from it by a sand-beadi, are ])ools of 
 
 water, resulting from the drainage of the mnck spoil 
 
 l>anks; these are the gi'eat collections ot' peat and 
 
 muck that \vere extracted from the bed the ])oii(l 
 
 and spread o\-er the tields in its \ icinity. With the 
 
 vegetable matters there occiirre(l considerable (|uan- 
 
 tities of bisulplniret of iron, and more or le^^ clayey 
 3 
 
14 
 
 or aluminous earth. As tlie heaps lay exposed to 
 the Aveather, the iron pyrites decomposed ; the sul- 
 phur, coml)ining ^vith atmospheric oxygen, formed 
 sulphuric acid, and the iron became an oxide, with 
 which a j^ortion of the sulj)huric acid uniting formed 
 a sulphate of oxide of iron ; ^vhile another portion, 
 uniting with the alumina of the clay, formed, with 
 the former, a dou1)le sulphate of alumina and iron. 
 The quantity of this salt was sufficient, Avhen scat- 
 tered over the surface of the heaps, to be every- 
 where perceptiTde during the warm weather in the 
 Summer, in the form of an efflorescence, and to com- 
 municate a decided sul])hurous odor to the atmos- 
 phere around. It is readily dissolved by water, and 
 is washed down by the rains to the lowest levels. 
 The ditches along the margin of the ])oiid are for 
 the purpose of catching this drainage, and prevent- 
 ing its entrance into the pond. This is, in great 
 part, effected by the sand beach ; l)ut, as the water 
 in the pooh rises and falls ^y\^]l that of the pond, 
 the communication between them is not entirely cut 
 off, and it is possible that some of the impurities of 
 the pools may filter through. The examination of 
 this water aff()rds an indication of the kinds of 
 impurities that may thus be introduced ; but it is 
 to be remarked that the quantity is likely to dimin- 
 ish, as the superficial layers of muck becoine ex- 
 
15 
 
 liaiistcd of tlu'ir saline iiiatci ials. Indeed, ]>y coni- 
 pai'ing tlie results of examinations made at the 
 interval of al)ont four months, I find the ])ro])ortion 
 of saline matter has already sensihly diminished. 
 
 The water of the ])ool at station 1'.) is remai'k- 
 al)le for its large proportion of im])urilies. It is of 
 a dee]) reddishd)ro\vn eoloi-, and strong styptic 
 taste, — an ounce of it gives distinct crystals of the 
 donl)le salt of sulphate of oxide of iron and alumina. 
 A gallon gives, by evaporation, a solid residue of 
 183.059 grains, consisting of inorganic matter, 
 T2 8.909 grains; and organic matter, with watei* of 
 crystallization, 59.750 grains. 
 
 The water from station 21 is highly colored hy 
 organic matter, and, in September last, it manifested 
 even to the taste the ])resence of a considerable 
 amount of the double salt already named. In De- 
 cember, however, this had nearly disa])])eared. A 
 galhm of tlu^ ^^■ater yielded, l>y evapoi'ati(>n, a solid 
 residue of 1*2. SlO grains, eonsisting of inoiganic 
 matter, T.<>74 grains, and oi'ganic matter, 5.7(Uj 
 grains. 
 
 These investigations sngu'est the following eon- 
 clu<ions : 
 
 1st. The most noxious imj)urities that find theii' 
 way into the water of the pond are (h iixcil fiom 
 sources that ai'e rapidly l»eeoming exhausted in great 
 
10 
 
 part. And, moreover, tliey undergo such clianges 
 in tlie pond that tliey are converted into harmless, 
 inert, and insoluble compounds, wliicli are likely to 
 remain, to considerable extent, as precipitates in the 
 pond itself, or in tlie reservoir at Kidgewood Hill, 
 wliere sediments can as^ain subside T)efore the final 
 distribution of the water. 
 
 2d. While the sup23ly of water is primarily- de- 
 rived from the purest springs of the diluvial sands 
 and gravel, the contaminations are almost wholly 
 furnished by the vegetable deposits, through which 
 the streams flow before they are discharged into 
 Jamaica Pond. Hence, the clearing out of these 
 channels is an ol)ject of pi'imary importance, should 
 any objections be found to the quality of tlie water 
 now furnished to the city. Some of the smaller 
 streams are decidedly sluggish, and their course is 
 through low swamps, of similar character to the bed 
 of Jamaica Pond before this was cleaned out. 
 
 The experience of another Summer will better 
 determine the expediency of prosecuting this work, 
 which, the further up the sources it is extended, 
 must unquestionably increase both the quantity and 
 the purity of the water supplied to Brooklyn. 
 Respectfully, yours, 
 
 A. K. EATON. 
 
 72 Beaver St., New York, 
 Jan. nth, 1860. 
 
V R E F A C E 
 
 It will he iioticHMl tliat tlic follow ing rcjxn't was 
 iviidcrcd ill ^Farcli, ls(')(i, l»ut,at the C()iiiinissi< )iici"s' 
 suggestion, a t'lirtlier iiKjiiiry into tlie whole amount 
 of fresh ^\ater discharu'ed from the drainau'e-hasiu 
 into Jamaica and Hempstead l>ays \\ as i-csolved 
 ujMHi ; and no favorable opportunity offering, while 
 active construction of the Conduit Extension works 
 was progressing, to j)rosccute the necessary (\\']H*i'i- 
 nients, a eom])letion of the re])oi't w ith these addi- 
 tions ^\'as conseipiently postjxmed until the Sum- 
 mers AVork was finished. It ^vas tliouuht hcst to 
 incor])orate the result of the investigations in rela- 
 tion to the hay into the hody of the rc])ort, rather 
 than append it in a sc])arate form. 
 
 Three maps anciv tirst made, two ol' them ex- 
 hihiting profiles ot* the country, on rather a larger 
 scale, and somewhat more in detail than is now- 
 presented ; it was considered, howcxt-r, de-iral»le to 
 condense the \\hole into a single I'epre^eiitation, as 
 c>lfering more read\ lacilitie^ tor comparison. 
 
18 
 
 To tliose who are not familiar witli tlie character 
 of country on tlie south side of Long Island, or with 
 the plan of water supply to the Brooklyn Works, it 
 may not be improj^er to briefly explain its main 
 features. 
 
 From Brooklyn, where the contour of the ground 
 is somewhat broken, the irreofular eminences are 
 collected together in the neighborhood of the village 
 of East New York, and then stretch, as a single 
 ridge, very directly eastward, dividing the Island 
 into two portions, — that on the north l)eing of an 
 aluminous, heavy soil, of which the ridge itself is 
 mostly composed ; while that on the south side is 
 entirely sand, of a very equal quality, being disin- 
 tegrated granite, probably deposited 1)y the ocean 
 currents against the base of the ridge, which seems 
 to have been the terminal morain of a glacier. This 
 sand-deposit, by constant accumulation, has grown 
 out into the ocean, and thus the plains have been 
 formed which constitute the gathering grounds for 
 our AA'orks. 
 
 The drainage of the country between the city of 
 Brooklyn and Jamaica has not in any way been 
 used ; l)ut, from the neighborhood of that village to, 
 and rather beyond Hempstead, the water yield of 
 the country has l)een appropriated. The drainage 
 of this district has collected itself into seven con- 
 
19 
 
 si(lt'ral>l(' st rc.-nii^, wc lia\(' <lr>iL:iiattMl as 
 
 Jamaica, SpringHcld, lirooklirM, Clear Slrcaiii, \'al- 
 ley Stream, Rockville ami llcmjjstca!! ('recks. Hie 
 flow of one ot* tlicsc, SpringHcld, lias not, as yct,lH'cii 
 included in the supply. Each of these streams, 
 havini!' a fall of al>out ei<>:ht feet ])ei' mile, and Leinir 
 from three to eiuht mik's long, lias l>een jxuided at 
 various ])laces since the settlement of the Island, 
 and the water used for mill |)urposes. A pond on 
 each stream ^^■as purcliased l>y the city of Brookh n, 
 and the right of taking the Avhole floAV gi'anted that 
 cor])oration. These ponds ^vere found to l>e tilled, 
 more or less, Avith decayed vegetal )le matter, oi' 
 muck, de[)ending in amount upon the length of time 
 they had 1)een (hmnn(Ml up. Sections of them are 
 sho^\-n on the ma]), an itli the depth of nuick found 
 in each. Xew dams were carefully consti'ucted, with 
 weirs and gatediouses of masonry. From each a 
 ])arrel-conduit of brick, varvinu' from '2 feet to 
 feet ('» inches in diameter, takes the yield ol' the 
 pond and emj)ties it into a lai'ge acjueduct, ANhich 
 lies ahout one third of a mile to the soutli, and the 
 whole collecte<l tlow i^ thence carrie(l lo a j>um])- 
 wcll, from whicli it is elevate<l, l>y two steam en- 
 irines, 17<' feet, into a ic^ervoir locate(l on the ridL:«', 
 about five mih'» fiom r)r<»oklyn City Hall, and from 
 this reservoir thence di-trihuted, i»y iron ]»ij>es, 
 
20 
 
 tliroiigliout the city. The bottom of the main aque- 
 duct, where it begins at Hempstead Pond, is about 
 feet above average high tide, and descends, as 
 it approaches the pump-well, at the rate of (3 inches 
 to the mile, its ^vhole lens^th beins; a little more 
 than 12^ miles. The water-surface in the supply- 
 ponds, when full, is from 8 to 15 feet above tide- 
 Avater. 
 
 The material composing the entire district being 
 sand, and the water, therefore, filtered, is very pure 
 and cool. By the arrangement of branch aqueducts 
 above described, each pond can be used or not, as 
 may be Avished, or the "whole at once, so tliat any 
 one of them may be repaired or cleaned As ithout 
 interfering with the delivery of the others. 
 
 It is hoj)ed that the fe^v facts developed in the 
 following report Avill hereafter l)e confirmed and 
 more thoroughl}' illusti'ated ])\ the department into 
 whose hands the charge of the Avorks Avill ultimately 
 fall. A thorough familiarity Avith the Avorking of 
 the system of sui)ply already brought into service, 
 and a full understanding both of the necessities and 
 capabilities of the supply-basin, may prove of much 
 use, not only to the city particularly benefitted, but 
 to an intelligent development of the Avater resources 
 of other districts. 
 
 TlIEODOKE WeSTOIS-. 
 
 January^ 1861. 
 
K E P O K T 
 
 Ja:\ik^^ p. Kikkwooi), Esq., 
 
 K)ujlnccr Ih'ooIJ ijn Wcdo' Worlx. 
 
 ^Iy Dkaii Siii : — Wlicn, in XovemluT last, you 
 desired iiie to ascertain tlie ae'Cfreo-ate drainao-e area 
 of the great hasin whence the su])})ly to onr works 
 is derived, I did not at once perceive wliat interest- 
 ing (picstions w(M'e C()ni])r(^liend('d in tliis examina- 
 tion, nor how far faitliful and continuous inves- 
 tig^ation was necessarv to determine witli accuracv 
 the extent and jx'cullarity of tliis su])])ly; and, 
 thougli yoiii' restrictions did not admit of my under- 
 taking a cai'ei'ul toj)ograi)hical and liydr<»metric sur- 
 vey of tlie district, I am convinced tliat, in j)rosecut- 
 ing my in(|uiries somewliat further than you, per- 
 lia])s, intelKhMl, y<.u w ill not onl\- see that the su1>ject 
 chiime(| this additional att<'ntion on our part, l)ut 
 will I'ecognize the importance ot' collectiiiL^- niucli 
 more careful and elalxn-ate data, from which to 
 deduce any just and relial»le results. 
 4 
 
00 
 
 The constant attention wWcli the construction of 
 the Conduit Extension required from the available 
 engineering force in the Company's service, prevent- 
 ed my taking up the drainage survey with any 
 vigor until the 5th December last, when, joining the 
 parties at my disposal, I was enabled, by uninter- 
 i*u]jted and rapid surveillance, to complete most of 
 the necessary field operations by the 1st January. 
 
 The interval which has since occurred has been 
 consumed in preparing the accompanying draAvings, 
 and collecting such information as I judged would 
 prove useful in explaining the character and capacity 
 of our storage T)asin. If this interval has seemed to 
 you unnecessarily prolonged, I trust the claims of 
 other portions of the work upon our time will suffi- 
 ciently excuse any apparent delay in submitting the 
 results of our labors. 
 
 It was made tlie especial ol)ject of the survey, — 
 
 1st. To ascei'tain the actual peri])hery of the 
 entire drainage district. 
 
 2d. To discover, as nearly as possil)le, the drain- 
 age limits of the different streams ; and 
 
 8d. To determine the depth of the subterranean 
 spring level below the surface. 
 
 As the readiest method of effecting these pur- 
 poses in the rapid manner proposed, it was decided 
 
23 
 
 to follow uj) the iiiiiiici-ous roads wliicli cut the 
 country in every (lireetioii, ascertaining their eoiiloiir 
 and neigldmring topogra])liy, and invariably deter- 
 mining the water levels in all contiguous wells. 
 Important vallcNs and streams which c()uhl not l»e 
 thus reached were separately sur\e\('d, and sulli- 
 ciently far to learn their extent and direction. 
 
 The ag^ofrcecate leiis^tli of line so run amounted to 
 miles (tlie ])osition and distribution of ^\llicll 
 is sliown (HI tlie accompany ing map). 
 
 The fre(pient intersection of these roads gave 
 al)un(hint o])portunity of correcting and verifying 
 all instrumental work, tliougli no error of any im- 
 portance was detected. 
 
 Some 25 mik^s of former surveys, by engineers 
 previously em])loyed on ])lans for the AVater Works, 
 and a portion of the j)i*ofile of the Long Island Kail- 
 way (l)etween Hempstead and Jamaica), obtained 
 fr(nn the office of the President of that C'om]»any, 
 were ap})roj)i'iated and used in the construction of 
 the maj> I'eferrecl to in this report. 
 
 ^'ou will ])crcei\(' that this ma]) is intende*! to 
 exhibit the extent and tbrm of the se])arate basins, 
 and to indicate, also, the length and beai'ing of the 
 m<»re imj)ortant vabeys and streams, both tlio^e con- 
 tributing to our su]>j)ly, and th<)se una\ailal>h' to 
 US. Tlie cont<>ur of the spring-water surface is 
 
24 
 
 designated by the Ijliie lines, wliioli are traced on 
 the map at intervals of 10 feet, between elevations 
 of 15 and 50 feet above mean hisfh tide- water. 
 
 Profiles of the ground smfacef and water bed 
 at various points are also given, the portion of each 
 which is colored blue indicating: the heicrht at which 
 the spring water is found above datum base. The 
 vertical lines on the profiles are the Avells whose 
 surfiices were ascertained by direct and careful meas- 
 ui*ement. Sections across the various supj^jly ponds 
 are added, in order to show the relative amount of 
 muck deposit Avhicli had accmnulated in each. 
 
 In looking over the map, your familiarity with 
 the region there represented renders it hardly neces- 
 sary for me to describe its ordinary features ; it, 
 liOAvever, may not he altogether improper to call 
 your attention to some of its more prominent pecu- 
 liarities in connection Avith the facts which have 
 been elicited by our sui'vey. 
 
 The northern limit of tliis basin is the well- 
 defined chain of hills, Avliich is a part of the great 
 dividing line of Long Island ; its southern boundary 
 is the line of arpieduct, now in process of construc- 
 
 * Wherever levels are mentioned in this report, they are invariably to 
 be referred to this datum-base used in the construction of our works. 
 
 f Elevations of the ground surface were taken at stations 200 feet apart. 
 
25 
 
 tioii ^\■lliU' its eastern and wcstci'ii extremities are 
 teriiiiiiated hy lines nearl} at liglit angles to the 
 ridge. The annual preei])itati(>n of rain and snow 
 upon the surfaee ineludcMl in these limits is the sole 
 souree of its ^vater supply. 
 
 This district, }'ou w ill see, readil\ divides itself 
 into two distinct portions : — 
 
 1st. The ridge and its slopes constituting a1»out 
 one t^velfth the drainage area, having a compact and 
 conglomerate soil, generally im])ermeal)le to Avater ; 
 and 
 
 2d. The table land lying at its l)ase comprising 
 the remainder, and liaving a soil of very porous and 
 ahsorl )ent character. 
 
 The crest of the ridu'e i^ exceedinu'lv irreu'ular, 
 and marked hy de})ressi()ns, Avhose suljstratum is 
 often a bed of ela}', which, collecting tlie surface 
 Avater of many acres, holds it in the form of mai'she^ 
 or small ])onds, and allows it to esca])e only l>y sl<>\v 
 tilti'ation and eva])oration. The southern slojx* of 
 the ridge is more uniform, and, turning off most of 
 the rain-fall uj)on the sand plain helow, may he 
 pr(»])erly considei"e(l a ])art of our gathering ground. 
 
 .\s the shore line of the l>ay and this ridge con- 
 
 * The ritic of Coiuluit ExU-n.sion lies so Tu-arly at ihv natural I'd^^e of tlu- 
 basin, that 1 have considered it nio^t convenient to assume it as our south- 
 ern boundary. 
 
26 
 
 verge toward tlie western extremity of the basin, we 
 find the elevations of both plain and ridge propor- 
 tionately diminishing toward that end, at an average 
 rate of 12 feet per mile for the former, and 17^ feet 
 per mile for the latter."^' The face of the hill slope, 
 as yon will remember, is very steep, having a mean 
 inclination of al)out one foot in six ; from its base 
 the table land thence falls towards the bay, at a 
 varying rate of from 12 to 27 feet per mile. 
 
 The contour of this taljle is mostly even, and 
 especially the eastern portion, AN'hich includes the 
 Hempstead Plains ; it becomes, hoAvever, more un- 
 duhiting as the Jamaica end is approached. We 
 find a large proportion of it under cultivation, or 
 open, — the forests, marshes, etc., not exceeding, 
 probably, one -seventh the entire area. After strik- 
 ing through the surface soil of shallow loam, a sub- 
 soil of clear, clean sand is universally found, an hose 
 constant character is undoubtedly preserved to a 
 great depth beneath ; and it is this great sand bed, 
 the interstices between whose particles, up to a 
 certain level, are filled with water, which constitutes 
 the storage reservoir whence our supi:>ly is drawn. 
 
 * AVhile the ridge is some niiles from tide-water at the east end of 
 the basin, it is but 21,000 feet, or 4 miles, at the Jamaica end. 
 
 An elevation of 366 feet was reached upon the highest knoll of the 
 Harbor hills, and one about 195 feet high north of Jamaica, 
 
27 
 
 Tlio subterranean surfaee tliis reservoir eoii- 
 toriiis, ill oviieral, to tlie slope of tlic ])laiii ; Imt, as 
 you would expect, it lias inueli riioic reirularity, and 
 it is only at the southern extremity of tlu' l»asiii, 
 where it lies very near the to]) of the ui'ound, that 
 any undulations are eons])ieuous. Occasional d(^- 
 ])artures or variations from this oc'iu-ral fact may, 
 however, he ex])lained hy the prol)a])le existence of 
 soiiK^ impeneti'ahle or disturl)ing stratum under- 
 neath ; such, for instance, as you Avill ohscrve in tlu^ 
 Hyde Park protile at Herrick's Pond, and hetween 
 Springfiehl and Prookficld in the Jericho turn])ike ; 
 and, in(hn^d, ^ve are ^\ ell ^\ arranted in ascrihing 
 them to this cause, since the excavations upon our 
 works have revealed cases of similai* ireoh^irieal 
 peculiai'ity and ^\ e may presume that the regular 
 le\-el of storage would still he found l)elo^\■, at its 
 proper elevation. 
 
 The uiiifoi'iiiity of the water slojx' will he seen 
 on comparing the grades of the separate ])rofiles; 
 thus, tlie rate 
 
 F(.r Ih'ookfield road is -2.4 feet ])(*!• 1,000 feet. 
 Springfield 2A\ " 
 
 Valley Stream" 2r2 " " 
 
 " Kockville ^' i>.4 " 
 
 * The bhu'-clay lietl fouiul ten foet uiuler the saiul. at !>tatioii oTO of Con- 
 duit Kxtension line-. a noticeable instance of this 
 
28 
 
 Indicating an extreme difference of but two feet per 
 mile, — a condition so invariable that we may reason 
 upon it witli great certainty, while it affords the 
 strongest testimony to the permanent character of 
 the supply. 
 
 Having now recalled to you these more prom- 
 inent features belono^ino; to the reoion under con- 
 sideration, I shall first direct 3 our attention to the 
 computed extent of various suT)divisions of the dis- 
 trict, and afterwards submit to you a few calcula- 
 tions, based upon what little information I have 
 been able to collect, which may possibly assist in 
 giving you some idea of the great capacity and con- 
 stancy of our storage reservoir. 
 
 The drainage ground comprises a total area of 
 73.64 square miles, liaving an average length of 
 about 12 miles, and a mean widtli of little more 
 than 6. It may be subdivided into six poi'tions : — 
 
 1st, Jamaica Creek and its tributaries, 10.88 sq. miles. 
 
 2cl, Brookfield and Clear Stream Creeks,. . . 8.87 " 
 od, Valley Stream, or East Tlook Creek 
 
 Branch, 0.38 " 
 
 4th, Rockville Stream, 8.31 
 
 5th, Hempstead Creek, 25.79 " 
 
 00.23 " 
 
 Gth, Unappropriated streams,* 13.41 " 
 
 73.G4 " 
 
 * The uncertain yield wliich is likely to be derived from the taps pro- 
 posed in the sides of the aqueduct, and the difficulty of ascertaining the 
 
29 
 
 Tli(Miii;i])])r<)])riat(Ml portion, (listiiigiiislitHl l)ytli(* 
 ])iiik lint ill tlu* ma]), may Ix' t'lii'tlier sulxlix idcd, 
 as follows : — 
 
 3.44 sq. miles, — Tiie region included hclwecn Conduit Ex- 
 tension and a line eonneeting the dams 
 of supply ponds. 
 
 5. GO Di-ainage of Springfield Valley. 
 
 1.72 " Valley Stream. 
 
 2.05 Foster's Brook and adjoining 
 
 streams. 
 
 i:i.41 
 
 It will he seen that 00.2 square miles, or 82 per 
 cent, of the whole district, contrihutes to the supply 
 ponds, \vliile the remainder passes its waters off 
 under our conduit, })y the culverts provided, and 
 they are thence carried to the sea. 
 
 Althoiiuh the aggregate area, as stated, is ])rol)- 
 a])ly very near the truth, the sul)divisions, as shown 
 in the ma]), must ht^ regarded as more uncertain. 
 
 Were ours a mere surface drainage, the ridges 
 hetween the sti'eams would indicate ti'idy the ])roper 
 water-sheds; hut since tliey are led mostly from 
 springs cro])])iiig out at \arious ])oiiits in tlieir 
 coni'se, all coming from the great 1('\ cl water-lxMl, 
 whose regnlar siirt'ace was remarked ahove, tlu* 
 
 distance bjick from these deliveries at whieli the water bed would be affected, 
 has led me to reject altoj^ether the re<i;ion drained by tlimi as a ]>ai t of our 
 gathering ground ; it must, however, be quite small. 
 
80 
 
 distance from the edge of the stream, where the 
 influence of each ceases, is very difficult to conjec- 
 ture. 
 
 Toward tlie mouths of tlie creeks, wliere the 
 undulation of ^vater follows the roll of the 
 ground, we may determine the separations quite 
 distinctly ; l)ut, as we approach their sources, where 
 no such correspondence occurs, we must evidently 
 locate them with great uncertainty ; it is prohable^ 
 indeed, that they merge into each other, very slight 
 causes controllino^ the direction of the discharo^e. 
 Between the base of the rido^e and the heading' of 
 the streams, a large space intervenes, through which 
 the water is very equally distributed, and which, in 
 fact, can pro])erly have no subterranean water-ridge. 
 
 The rate of fall of the stream does not commonly 
 coincide witli the i*ate of the underground water- 
 slope, — the foi'mer 1)eing ordinaril}' al)out 10 feet 
 per mile, while the latter, it was discovered above, 
 preserves a uniform grade of 1 2 :| . Vs^e^ consequently, 
 find the surface of the stream, as it approaches the 
 southern edge of the basin, flowing al)ove the stor- 
 age surface ; if, therefore, an adjoining l)rook is in a 
 loAver valley, it nmst apparently draw beyond the 
 middle of the distance between the two. Brookfield 
 Stream, for instance, is ponded at an elevation of 
 15.4 feet, while Clear Stream, adjacent, is but 10 ft. ; 
 
81 
 
 and ^^'(' should, course, iiit'cr that tlic latter would 
 yield a larger j)ereentage of watei', in proportion to 
 its leugtli and iiuj)()rtaneo, tlian the tonner ; and, in 
 .some degree, it pi'ol)al)ly does, tliougli it is luueli 
 less than Avould l>e su})[)osed, and not enough to 
 materially afKeet the location of tlie di\ ide. 
 
 AVitli reference, tlien, to sucli conditions of dis- 
 charge as our limited observations suggested, 1 liave 
 attempted to trace tliese water-ridges, indicating tin* 
 surface-ridges, l)y lines of shading, and making tliem 
 commonly tlie guide for the direction of tlie reser- 
 voir outline underneath. 
 
 If, now, \\ (' adopt these subdivisions, as estimated 
 in the above areas, and compare each Avitli the mini- 
 mum floAv of the drainage stream belonging to it, as 
 given in your re[)ort of January, 1858, the following 
 tal)le is o])taine(l : — 
 
 
 
 1 
 
 Am't (low per 
 
 No. gal.'s. per 
 
 No. pals. 
 
 Districts. 
 
 Area drained, 
 
 day, ' 
 
 day per sq. 
 
 per day 
 
 
 s(i. niilfs. 
 
 N. Y. gals. ' 
 
 mile. 
 
 per acre. 
 
 .Taiiiiiita 
 
 10.88 
 
 ;^.()r);>.7i)2 
 
 280,677 
 
 439 
 
 Brookficld ami Cl. St. . . 
 
 8.87 
 
 2.<U7,r)3() \ 
 
 295,1(10 
 
 461 
 
 
 (•>.:', 8 
 
 2.;588.:i(»r) ! 
 
 371,342 
 
 585 
 
 liockville 
 
 8.:U 
 
 2.569.320 ' 
 
 309,184 
 
 18;] 
 
 
 2.-). 79 
 
 7,651,321 
 
 296,677 
 
 463 
 
 Total and mean 
 
 (ift.'J!:-! 
 
 18.280.530 1 
 
 303,515 
 
 47t 
 
 
 i:;. 11 
 
 1,00:3,230 
 
 303,515 
 
 474 
 
 
 ; 73.64 
 
 22,343,760 
 
 
 
The unappropriated portion in the table, you 
 will notice, is calculated to yield 4,063,230 gallons, 
 — a quantity answering to the mean drainage per 
 square mile of the other five districts. 
 
 It is seen, from the above schedule, that Valley 
 Stream gives the highest I'ate per square mile, and 
 Jamaica the lowest; while the others differ very 
 little from each other. In the case of Valley Stream, 
 it is not inq)robal)le that too little area is assigned 
 its drainage territory ; still, the flow of the stream 
 is very direct and single, its only tributary uniting 
 with it below our dam, and largely augmenting its 
 volume. The circumstances of a free dischars^e of 
 the bordering springs into its channel is very favor- 
 able, the ridge on either side l)eing high, and the 
 dip of the Avater-bed strong toward the stream. 
 
 In comparing, hoAvever, tlie form and features of 
 the Jamaica district A\'ith the remainder of the T)asin, 
 the mrface character of its drainage is very appar- 
 ent. Small brooks or arms shoot off in every direc- 
 tion, and the springs discharge feebly, the mean 
 storage-head being but 12.9 feet above the plane of 
 the full pond into Avhich the Avhole water is deliv- 
 ered. Beaver Creek, which rises near the T)ase of 
 the main ridge, and is more immediately supplied 
 by lateral springs, is its coolest, clearest, and most 
 constant tril)utary, but yet does not contribute 
 
eiiouo'll to o'ive characU'r to (lie pond, wliosc Avatci' 
 is noticeal)ly difl'ereiit i'low) I he otlu rs lo tlic 
 east. Our experience in its management also indi- 
 cates that it is more readily and to a greater extent, 
 affected l)y Hoods. 
 
 Of tlie remaining sub-districts, notliing in tlieir 
 physical conditions recpiires especial remark; tlie 
 flo\v of tlieir various drainage streams is (piite 
 similar and unitbi'm, both in volume and (piality. 
 
 Considering the resulting mean deri\'ed from 
 the tal)le as approximating the trutli, Ave liave a 
 toleraldy relialde calcuLating unit for the natural 
 yield })er s(|uare mile. If Ave assume, therefore, 
 datum high tide i)lane as the bottom of our whole 
 storage district, and neglect all al)sorl)ing capacity 
 beloAV that plane, by tirst determining the average 
 heisfht of saturation throusrhout the basin, and the 
 amount of watei* ^^ hich each cubie f>ot of sand \\ \\\ 
 hold in its interstices, we may readily com[)ute the 
 whole (juantity stoi*ed in the district. 
 
 1^'roni (»ur niaj), the water surface is aseertained 
 to ha\(' a mean level of '>1 feet above the ]»lane 
 assume(l : and, from the results of several e.xpeii- 
 nients directed to this end (details of which ai-e 
 gi\-en in Table A, at the end ),(>..')( ) i> lixed .-i^ the 
 storage sj)ace in each cubic foot (»f (»rdinary material 
 composing the sand-l)ed. The area of the l»asin, 
 
34 
 
 then, being 73.64 square miles, or 2,052,670,816 
 square feet, by applying the units above our calcu- 
 lation gives us 19,459,319,335 cubic feet water in 
 store, — a quantity sufficient to yield 20,000,000 gal- 
 lons per (lay for nearly nineteen years, apart from 
 the yearly addition by ordinary precipitation to its 
 reserve. The same reasoning may manifestly be 
 followed in estimating the reserve of each sub-area, 
 new depths being found for every separate district. 
 
 The subjoined table, in Avliich I have computed 
 the depths above the plane of each pond surface 
 Avhen full, will give you their relative storage capac- 
 ities above those levels : — 
 
 
 
 ■ storage 
 pond. 
 
 
 
 
 
 DISTRICT. 
 
 Level of 
 full pond 
 
 Surface of 
 above full 
 
 Area 
 of district. 
 
 Min. 
 daily 
 flow. 
 
 Amount 
 held in store. 
 
 No. 
 days 
 reserve. 
 
 
 Ft. 
 
 Ft. 
 
 Sq. feet. 
 
 Cub. feet. 
 
 Cub. feet. 
 
 
 Jamaica, 
 
 Brook field, ) 
 
 Clear Stri-aiii, . . . f 
 
 Valley Stream, .... 
 
 , PvockVille, 
 
 1 Hempstead, 
 
 l| 
 
 8.0 
 15.4 
 10.0 
 12.8 
 13.0 
 10.6 
 
 12.9 
 
 20.3 
 34.4 
 38.4 
 
 299,570,000 
 IVY.T^o.ooo 
 
 231,C.'j:),«'i>() 
 7l9,26o,0»)(» 
 
 391,010 
 
 30.-,, 801 
 979,683 
 
 1,162,032,030 
 
 1,083,564,000 
 •J,:;93,844,375 
 6,866,754,472 
 
 
 
 2,792 
 
 3,543 
 7,276 
 7,009 
 
 So large a I'eserve fis is here indicated for each, 
 must prevent the flow of any of the streams from 
 becoming seriously diminished by drought ; nor, 
 probably, would the stored amounts vary much from 
 
35 
 
 year to yeai", llie extra i)i'('('ij)itat ioii ])as>;iim- oil' l)y 
 increased discliai'Li'e t liroiiLili the sti'caiiis. 
 
 We may now, 1>\ takinu" tlie mean rain Tall njjon 
 the general district, jnduc still tnrt her < )t* it s caj)acity 
 and constancy, and discoNcr liow nincli may he 
 dra\vn away witliont injni'v to this reserve. 
 
 Estimating tlie avei'age j)recij)itation at 42yy- 
 inclies ])cr year on each sijuai'e toot ot* area,"' \ve tind 
 that it wouhl liave required iij) wards of tliree years 
 to liave tilled the Lasin witliont any w aste occurring, 
 either troni eva])oratlon, vegetaLle al)soi'j)tion, oi' 
 hy discliarge througli the springs and water coui'ses ; 
 and that, allowing tor these natural h)sses, it would 
 have taken not less than twelve veai's to l)rinL'' the 
 reserve up to its present level. 
 
 We see, C()nse(piently, that the small \ ai'iations 
 of a season's, oi* even a year's, rain-fall can affect the 
 resei've height hut slightly, compelling us to I'ecog- 
 nize AN'ithout hesitation the certainty an<l ])erma- 
 ncncN' of onr snj)])ly. f' 
 
 Being convinced, then, of its great ca])acity, it 
 
 * This moan is made up tVom the three tables (W, C, and D) apijended. 
 The Jamaica record, you will j)ereeive, is tlu-own out a< entirely unre- 
 lial.le. 
 
 f The <;-eneral ti-iith here stated, respeetiiis; the constancy of the water- 
 surface in tlie moan area of the basin, admits, however, of some ijualitieation 
 when applied to it>< -southern or dis( haruiui;- edoc. As befi.ir»' remarked, the 
 level of this rei'/ion of the ri-serve lies \ cry near the -urfaci.' of the Lrrountl. 
 
86 
 
 becomes interesting to know wliat proportion of tlie 
 annual rain-fall is passed off tlirougli our supply- 
 streams, and made availal)le to us hy tlie present 
 location of tlie works. And tliougli we liave made 
 no experiments sufficiently definite to determine tlie 
 evaporation, or vegetaT)le absorption in our own 
 district, Ave still have enougli data to compute the 
 total percentage of loss, and thence judge, from the 
 
 and the rain-fall, readily penetrating to it, produces fluctuations in its height, 
 corresponding, in some degree, to the variations of precipitation. 
 
 The following table of comparative elevation of several pits and wells 
 near the line of our works, taken at different periods, to which I have at- 
 tached a profile of rain-fall for corresponding periods, will illustrate this fact 
 to some extent : — 
 
 
 
 
 Elevations above tide-base. 
 
 ■| 
 1 
 
 
 
 
 
 
 
 
 
 ! 
 
 Extreme 
 
 1 
 
 
 WELLS. 
 
 u x 
 c '-' 
 
 3 
 
 
 
 o 
 
 
 fluctuations. 
 
 
 
 
 "-J 
 
 
 o 
 
 S5 
 
 
 
 
 
 
 Feet. 
 
 Feet. 
 
 Feet. 
 
 Feet. 
 
 Feet. 
 
 Feet. 
 
 
 
 Xo. 1, 
 
 2.94 
 
 
 1.52 
 
 2.35 
 
 3.03 
 
 1.51 
 
 Earth, covering from 2 to 
 
 { 
 
 " 2 
 
 3.64 
 
 
 
 2.63 
 
 3.38 
 
 1.01 
 
 5 feet deep, 
 
 
 " si 
 
 7.70 
 
 
 4.81 
 
 6.18 
 
 7.31 
 
 2.89 
 
 1 
 
 " 4, 
 
 6.72 
 
 
 
 5.40 
 
 5.97 
 
 1,32 i 
 
 
 
 " 5, 
 
 6.08 
 
 
 5.96 
 
 5.91 
 
 
 0.17 1 
 
 Earth-covering from 8 to 
 
 1 
 
 " 6, 
 
 
 1.35 
 
 
 1.36 
 
 1.70 
 
 0.35 i 
 
 1 2 feet deep, 
 
 
 " 7, 
 
 
 5.66 
 
 5.72 
 
 6.03 
 
 
 0.37 
 
 
 " 8, 
 
 
 
 7.17 
 
 7.44 
 
 7.31 
 
 0.27 
 
 A comparison of the table and profile would indicate that, though the 
 rain-fall of the Summer months considerably exceeded that of the Autumn, 
 yet the surface of the water bed sunk until cool, unevaporating weather set 
 
37 
 
 common experience in otlier regions, ^vllat ])r(>])oi"ti(>n 
 properly Leloni^s to these two. 
 
 In } onr I'eport of 1858, }'()n collected some iiitor- 
 mation relating to surtace-evaponition, to Avhieli I 
 have l)een nnal)le to add anything more reliahh' or 
 extended, ])e}'ond the mere general inferences an hich 
 
 Prohi.k of JLun fai.i. from Mav to XovKMnKR, 18r)7 (incu sivk). 
 
 in; mill \vc iiiu>t presiiiuc, tlicn-forc, thai iicai-ly all llic pn-cipitatioii of tlio 
 liot inonlhs was tlissipated before it reached the under-j^round reserve. 
 
 You will observe, also, that the deeper wells (tlujse liii^licst above datum) 
 were i^rnerally more eoiistaiit, — the extreme ibu tuation of Nos. T). 0, 7, and 
 8 beini; small beside Xus. 1, 2, ;i. ami 1, which ha\i' much less earth 
 covering. 
 
 () 
 
38 
 
 are inapplicable to special districts like our o^yn. 
 Mr. Stirrat, however, whom I think you quote, in 
 evidence before the Parliamentary Committee of 
 1850, states that, Avhile Mr. Thom had previously 
 reckoned on a loss of 66 per cent, of the annual 
 rain-fall in the Paisley district, subsequent experi- 
 ence had proved that it was but 33 in those gather- 
 ing gi'ounds, — an amount much below the common 
 estimate. Mr. Donaldson, before the same commit- 
 tee, affirms that, at Eichnioiid Park, but 10 out of 
 25 inches fall ^vas available ; in other Avords, that 
 60 per cent. Avas lost. Both these districts ^vere 
 largely drained by the subsoil system. 
 
 Mr. Ellet, in a report rendered Se})t. 11th, 1819, 
 and puljlished among the Smithsonian contributions, 
 as the result of careful observation throughout the 
 feeding district of the u])per Ohio, states the mean 
 loss to be 60 per cent. ; and I think it Avill ])e found 
 that the most intelli2:ent estimates rather exceed 
 than tall l>elow this figure. We nuist expect, con- 
 sequently, in our sand countr}', to calculate for at 
 least an ecjual amount, and, as the following compu- 
 tations Avould suggest, possibly still more. 
 
 If the average flow of any one of our streams he 
 deducted from the mean annual rain-fall upon the 
 districts named by it, Ave have at once the comj^ara- 
 tive available percentage. I have fixed the average 
 
39 
 
 flow, in the ahsenee of any oontinuons record, at 
 two tliirds more tlian the niininiiiin s(4 (h>wn in 
 }'our re])ort a1)ove reteii'e(l to; and tliougli ^'ou 
 wonhl ])resiinie tliis to ])e large, you ])ereeive, 
 from tlie tahle helow, that tlie actual k)ss in tlie 
 district is so o-reat that consi(h*ral)le differences in 
 the daily discharge of the streams would not 
 especially atfei-t the average results : 
 
 i 
 
 DISTRICTS. 
 
 Area 
 drained. 
 
 Total yearly 
 rain. 
 
 Min. 
 flow 
 per day. 
 
 Ave. 
 flow 
 per day. 
 
 Total 
 yearly 
 "flow. 
 
 
 
 Per centum 
 of loss. 
 
 Jamaica, 
 
 Brookf'd & Ci. St. 
 Valley Stream,. . . 
 
 Rockville, 
 
 Hempstead, 
 
 Sq. feet. 
 
 299,570,000 
 240,155,000 
 177,750,000 
 281,625,0(X» 
 719,205,000 
 
 Cub. feet. 
 
 1,000,477,800 
 871,3^8,700 
 629,235,000 
 819,952,500 
 
 2,^6,198,100 
 
 Cub. ft. 
 
 391,010 
 835,280 
 805,801 
 32S,97> 
 979,683 
 
 Cub. ft. 1 Cub. ft. 
 C52,(HMI 23^,(ls(),0(M) 
 5.">S,800 208,962,(K)0 
 510,10(1 lS(i,ir)(t,004) 
 548,500 2(M».202,5<H) 
 
 l,6;32,650j 595,91 7,250 
 
 77 S-10 
 76 6-10 
 70 4-10 
 75 6-10 
 T6 (>-10 
 
 ; Total and mean, . . j 
 
 5,927,252,100 2,;340,752 3,902,05« | 
 
 1 1 1 
 
 75 4-10 
 
 These ])ercentages ai'e the losses in each ])articu- 
 lar sul)-disti'ict ; l)ut, to reach the ti'ue mean for the 
 wliole Lasin, we must add to that given in the talde 
 the amount due u])()n the una})})r()priated area, wliicli 
 is found to l>e l,82r),9r)0,()()0 cubic feet, — increasing, 
 conse(iuently, the total mean to 7S ]^er cent. 
 
 A \'ery considerable ])ro})ortion of this must he 
 credited to the ^vaste from springs erop])ingout Ixdow 
 the line of our su})ply reservoii's, ]>ut which are fed 
 from the same storage. \\\ gaugings made on two 
 streams (^Watts and lirooktleld ), detailed reports of 
 
40 
 
 wliicli I returned to you in August last, and wliicli 
 you will find in tlie Appendix (marked E and F), 
 the increased volume for eacli, at somewhat less tlian 
 a mile l)elow tlie city's present ownersliiji, was dis- 
 covered to be yV more at a time of minimum flow. 
 This ratio would undoubtedly l)e reduced during a 
 period of maximum or average discharge, when no 
 additional want could be felt, and need not, there- 
 fore, be considered. At the a1)ove rate, then, 15 per 
 cent, of the precipitation would T)e due to this sub- 
 terranean loss, — leaving, therefore, 08 per cent, to ])e 
 divided between the necessities of vegetal)le life and 
 the waste of evaporation. 
 
 The aA^erage daily flow, it is seen from the state- 
 ment in the table just given, yields us upwards of 
 30,000,000 gallons, ^vdiich, could we avail ourselves 
 of, the 15 per cent, here indicated would give us a 
 constant delivery of 50,000,000 gallons per day, 
 and, with the additional ISyV^ s(|uai'e miles of our 
 unappropriated sub-district, a further increase to 
 61,000,000, or a minimum equal to 40,000,000 gal- 
 lons, irrespective of the storage reserve, — all which 
 may be wholly procured from tlie territory lying 
 above the line of Conduit Extension. This, then, 
 may be regarded as the natural and available quan- 
 tity within the reach of our works, as they are now 
 located and constructed ; and I have, therefore. 
 
41 
 
 directed my liKjuirics almost exclusively to tlie 
 reliable determination oj'tlie yield ol'tliis reiiion. 
 
 But, it A\ill be ])(M'ceived that tlie whole district 
 lying Ix'tween this line and the shore of Jamaica 
 ])ay lias not, thus far, entered into my estimate. It 
 must, liowevei", deliver ])ro])ortionally a much larger 
 (quantity than any other: since, in addition to tlie 
 regular rain ])recipitati()n u])on its surface, w hich, ot 
 course, would er[ual the amount per square mile 
 assumed for the main district, it yields, also, all the 
 unestimated surplus that may have come down to 
 it from tlie higher grounds Avhich anc liaxc been 
 considering. I have attempted, therefore, to ascer- 
 tain this important increment, in a general way, by 
 noting the changes in the s])ecific gravity of watei* 
 alono; tlie shore of the bay at dilfereiit states of the 
 tide, and afterward rouglily computing a mean j)er- 
 centacje for the daily infusion of fresh water cominfr 
 from our entire drainage district, and subse(piently 
 deductino^ the known yield of the streams. 
 
 A carefully tested hydrometei' was used tbr this 
 j)Ui-])ose. The ivsult of these observations is given 
 in the table (marked II ) in the A])pendix, — each 
 recorded exj>eriment, it ma\ be remarked, being the 
 average of a nundx-i' of ti'iab. 
 
 The shore edire boundini:" our drainaL^-e district 
 has a leULi'th of rather more than f<»ui' niile< on 
 
42 
 
 Jamaica bay, and about three and one half on 
 Hempstead bay. At various points on this line the 
 several streams which at present supply our works 
 have their mouths. Abandoning now any attempt 
 at a calculation of the Hempstead line, upon which 
 no experiment has been made, we find that Jamaica 
 bay has a total water area of about 23^ square 
 miles, with an average water depth, at Ioav tide, of 
 about four feet, giving us 2,995,110,400 cubic feet 
 of water. Estimating, from the talde of observa- 
 tions, the fresh water infusion to be 10 per cent, of 
 the whole quantity, we have 295,511,040 cubic feet 
 as the amount in store in the whole bay at low 
 water, when the springs and streams are discharging 
 most abundantly. Assuming one fourth of this 
 quantity only as coming from our supply district, 
 there remains 7^,827,760 cubic feet. On the suppo- 
 sition that the waters of the l)ay are not wholly 
 renewed oftener than thrice per month, -J-^- of the 
 above quantity would give us the whole daily fresh- 
 water delivery, equal to 7,^82,770 cul)ic feet. The 
 minimum yield of the streams of all the territory 
 north of Conduit Extension, as stated in the early 
 part of this report, is 22,848,760 gallons, or 
 2,860,920 cubic feet ; of which, however, the flow of 
 Rockville and Hempstead Creeks, with their tribu- 
 taries, is to be deducted, since they empty into 
 
43 
 
 ni'iii])stea(l l)a}', — leaving, tlu'ivt'oiv, l,r);)L\(iln (111)10 
 feet to ]>e taken from tlie whole computed discliarge 
 into Janiaira ]>ay, and w liich \vill tlicn i)e r),S,S0,766 
 (•ul)ie feet, or 47,*ii^l>,000 irallons. llw wliolc district 
 comprised between the (/ondnit Kxtension line an<l 
 the shores of the Lays amounts to nearly l<>yV"o- 
 s(|uare miles, of wliich, discharging into Jamaica 
 J^ay, delivers the above minimum of 47,*2:21>,UOO 
 gallons, — at a rate, consequently, of 4, U 7 1,400 gallons 
 per s(|uare mile. The remaining poi-tion of ()jVo 
 s(piare miles, discharging into Hempstead bay under 
 exactly analogous peculiarities, Avould aftbrd, there- 
 fore, at the same calculation per scpiarc mile, a 
 further amount of 34,402,088 gallons. 
 
 Upon collecting all these above quantities, and 
 addiuii their difterent results, Ave reach the followinir 
 summary : — 
 
 ll 1 
 
 J. F<»r the aN iiil;il)Ir water (Idivciy iiitn 
 the present works, as aseertaiiied )>v 
 earel'iil cau^^iiifj, wc have, tor 
 
 '2. F<»r (Iraiiiajre of surplus Mater into 
 Jamaica Vjay, as ascertained l»y Ily- 
 
 \ 1 
 
 Pq. 
 miles. 
 
 ! 
 
 N. Y. gallons. 
 
 73.64 
 50 
 
 1 
 
 22,343,760 
 47,221>,000 
 
 1 
 
 34,40-2,088 
 
 For drainajn^ of sur[>lus water int(» 
 Hempstead hay, \n comparative 
 
 1 
 1 
 
 T..tals 
 
 
 lO.S. 97 1.760 
 
 
 
44 
 
 It may very properly be urged, tliat the data 
 upon wliicli items Kos. 2 and 3 have been computed 
 are entirely vague and insufficient, and would prob- 
 ably be largely affected l^y many natiu'al contin- 
 gencies wliicli have not been investigated or alluded 
 to. It may ])e seen, however, if we return to an 
 examination of the more reliable figures gathered 
 from the facts relating to the district Avhich we have 
 already appropriated, that it was there found that a 
 loss of 78 per cent, of the annual ])recipitation was 
 very satisfactorily determined. This loss, then, car- 
 rying out that computation, would anioimt to 
 79,218,828 gallons, and, added to the quantity 
 actually gauged, viz., 22,348,760 gallons, gives us a 
 daily delivery of 101,562,588 gallons. If, also, to 
 this be added the same rate of precipitation upon 
 the shore district, amounting to 23,345,400 gallons 
 more, Ave have a grand total precipitation, over 
 the whole DOylo s(juare miles, of 124,907,988 gal- 
 h^ns' equivalent, — allowing us, you will perceive, 
 21,000,000 gallons daily surplus, or nearly 20 per 
 cent. al)ove my hydrometric estimate, which ^ve 
 may credit to the necessary vegetable waste, and to 
 the evaporation. Hoav this evaporation might be 
 lessened ])y careful subsoil drainage,'"' and thus a 
 
 * It seems to be commonly conceded that nearly the -whole rain-fall, 
 during the months of July, August, and September, is evaporated before 
 
still further n)ntril)uti()ii to tlic rcsoinvcs of our 
 su})])ly-l)asiu secured, 1 do not ])ro])ose to iii([uir(', 
 iny object luiviiig l)een simply to call your attention 
 to tlie general capacity of the basin under circum- 
 stances of its j)resent natural yield. 
 
 But it is wca'th w hih' to consider, in case the 
 city ever contemidates an extension of her ^vorks, 
 whether some way could not he devised for collect- 
 ing and securing a portion of the great waste ^vhi(•h 
 has been sliown to occur, and thus avoid the larger 
 outlay likely to be needed in the purchase and 
 adaptation of new territory to the ])urposes of 
 increased supply. 
 
 In view of such a necessity, the value of a 
 thorous^h and continuous series of observations and 
 experiments becomes very apparent, and the pro- 
 priety of instituting some system of this kind ^\ ill 
 undonbtedlv suofo'est itself to vou. 
 
 I ha\-e appended tables of rain-fall for Fort 
 Hamilton, Fort Colundms, and Flatbush, with ])ro- 
 files of various monthly and yearl}* averages, whose 
 res])ective lieadings ^vill suiliciently ex])lain them. 
 
 I havt^ not thought it ])i'oper, in the limited 
 range of this investigation, to submit anv facts 
 relating to tlie character and ([uality of tlie water 
 
 reathiiii; tlu' iiiulcricrouiul stonigi' ; tlie spriiiijs and stream!*, consequeuti y. 
 (.lurinu: tliis time, draw wlu.lly \\\n>u tlie reserve. 
 
46 
 
 from tlie different streams, since it must evidently 
 be considered a very distinct and special l)rancli of 
 inquiry. 
 
 It gives me great pleasure to acknowledge the 
 important assistance of Messrs. Martin & Whitman 
 in the surveys, and of Mr. Williams in the accom- 
 panying map. 
 
 Very truly, 
 
 THEODOEE WESTON. 
 
APPENDIX. 
 
V P P E N D I X . 
 
 [A.l 
 
 EXPERTMENT> MADE TO DETERMINE AnSORIUNG CAPACITT OF SAND 
 AND GRAVEL. 
 
 .The experiments were made in a tifjhl box, rontnining one cubic 
 foot, the box being first filled tvith the sand^ and water afterward 
 added. 
 
 No. 1. Sand loosely thrown in, 0.300 cub. ft. water. 
 
 2. 0.350 " " 
 
 3. " " 0.310 
 
 " 4. " " " 0.325 
 
 " 5. '• " 0.350 
 
 0. •• 0.37 
 
 tamped with shovel. 0.270 
 
 8. " rammed very closely, 0.230 •• 
 
 9. Coarse sand, loosely thrown in, ,.0.320 " 
 
 10. " 0.32S 
 
 Jl. " 0.310 
 
 12. Sand and gnivel, loosely thrown in, 0.2r»0 
 
 13. " " " 0.275 " " 
 
 11. " " 0.323 " " 
 15. " " " " 275 " " 
 
50 
 
 No. 16. Grarel, clear, loosely thrown in,. . . .0.360 cub. ft. water. 
 " 17. - ... .0.358 
 
 " 18. " ....0.350 
 
 " 19. • • ....0.345 
 
 " 20. ^' " ....0.350 
 
 " 21. ... .0.363 
 
 22. Broken stone, specification size,*. . .0.520 " 
 
 * \iz., 8 cubic inches. 
 
51 
 
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52 
 
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58 
 
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55 
 
 J A M AI ( - A , J II I If '^S /// , I .s:)0 . 
 
 J. P. KiRKwooD, Esq. 
 
 Dear Sir: — In obedioiicc to your ^\ ishes, I Iiave hastily 
 ondoavorcMl to ascertain tli(^ additional flow <•!' water l)etween our 
 Valley-Stream Reservoir and Watts' Pond, next helow on the 
 same stream ; and that, also, between Brookfield Reservoir and 
 Conselyea's Pond, next below. 
 
 Of the first ease, I am sorry to say that, owing to the irregular 
 and capricious use of water in the mills above on this stream, I 
 found it impossible to obtain any reliable gaugings in the short 
 time at my disposal, and have, therefore, thought it best to omit 
 the record. 
 
 F()r the latter, however, the sul)ioined table will indicate to 
 you the comparative increase of which you wished to assure 
 yourself; the gaugings were taken under favoralde circumstances 
 of flow, and, as you will perceive, show a very uniform register. 
 
 Brookfield (Simonson's) Stream receives no noticeable acces- 
 sion tV<»m any bi-ancli or ti-ibutaiw ])etween the tw(» ponds undci- 
 observation ; but the whole intervening gi-ound on either side of 
 it is full of springs, which dischai-ge into the current very freely. 
 The distance from Brookfield Reservoir to Conselyea's Pond is 
 r),'2()0 feet. 
 
 Tilt' luctliod of gauging was as t'oHnws : At I>rookfirld Kcscr- 
 voir our present weir of masonry was used, and the de{)tli ol'd.iu 
 on the (jver-fall measurc(l a few feet back in still watci-, l»y a 
 hook-gauge, apitTn'tl to a lixcd graduated rotl. This wcii- has a 
 width of I J ,Y- feet, an<l, as you will sec by the aniu-.\ed table. 
 
56 
 
 the depth of flow over it did not reach two inches ; on applying 
 Mr, Francis' formula, therefore, to the calculations, inasmuch as 
 its conditions were not completely filled, I have modified it 
 slightly to suit this particular case. No perceptible contraction 
 occurring, I have neglected the deduction for effective length, 
 0.2 and corrected the constant 3.33, — the formula, as used, 
 standing thus : — _^ 
 
 At Conselyea's, however, a weir Avas insertedWiT the mill- 
 sluice, following closely the form of construction recommended 
 by Mr. Francis. The width wa^|;^de 2y/o feet, the height of 
 fall nearly four feet, the streani^uniformly flowing more than 
 eight inches deep over it, — securing us, consequently, a very 
 accurate application of the regular formula, 
 
 ^=3.33|^^X^-0.2 H). 
 
 The gaugings were made simultaneously at both ponds every 
 three hours, on the 26th, and every hour, from 9 A. M. to 6 P. M., 
 on the 2Tth, — the full flow of the stream being reached about 
 2 P. M. of the second day, and continuing quite regular up to 
 the time our observations ceased. 
 
 The increment, vou will discover, amounts to* about one and 
 a half millions of gallons, — a very important and suggestive 
 diflerence. 
 
 In the case of Valley Stream, 1 should l)e glad to repeat my 
 observations with more care, and sufficiently long to ascertain 
 the analogous increase which comes into that stream below our 
 reservoir. 
 
 I remain, very respectfully. 
 
 Your servant, 
 
 THEODORE WESTON. 
 
59 
 [1^1 
 
 Jamaica, Aifr/usl 23f/, 1859. 
 
 Mt/ Dear Sir : — Since tlic date <»f* my last stateiiiciit to yoii 
 concerning the relative increase <»r How Ijclweeii the ^'alley- 
 Strcam Reservoir aiicl AVatts' Pond, l)elo\v, on tlie same stream, 
 I have regauged tlic delivery at hotli these ]>oints with some care, 
 the resnlt ofwliicli is apjx'iided in the accompanying record. 
 
 Having etrectuaily removed all causes of irregularity that 
 were discoverable, I continued the gaugings for some time after a 
 uniform flow was reached, in order to assure myself, hcyond a 
 doubt, of a correct determination of the difference sought to be 
 established. 
 
 The weirs used at the j^resent trial were constructed some- 
 what diflx'rently from those first emi)loyed. 
 
 At Valley-Stream Reservoir, the present over-fall of nnisoni-y 
 was narrowed by a breast-board, in which a weir, 7 feet wide, 
 was cut out. It was placed on the outer edge of the masonry, 
 and had a height of yYo Jtl^ove it. The arrangement will be 
 undei'stood fi-om Figs. 1 and '2. 
 
 Reservoir Wtpler sur^force 
 
60 
 
 The water was retained in the reservoir until its head had 
 reached foVo ^t- on the weir, — at which point, as will be seen 
 by the table, our observations commenced. 
 
 At AYatts' Pond, below, the weir was placed in a rectangular 
 sluice-way which belongs to the mill on that pond. This sluice- 
 way Avas about 15 feet long, with a width of SyV^^^ feet. The 
 over-fall bar was made the entire width of the sluice-way, and 
 inserted about 3 feet from its lower end. 
 
 Our observations began at 11 A. M., August 4th, and ended 
 at 6 P. M., August 8th. From August 4th until 6 A. M. of the 
 8th, the gaugings were noted every two hours ; and from 6 A.M. 
 to 6 P. M., on the 8th, they were registered every hour. As in 
 the former trial, a hook-gauge was used, and readings taken 
 simultaneously at both ponds. 
 
 The flow, it will be noticed, increased quite uniformly up to 
 2 P. M., August 5th, at which time a sudden rise occurred in the 
 reservoir, owing to the discharge of the waters in the mill-ponds 
 above, — which, however, from this date until the conclusion of 
 our gaugings, were placed under our control. The natural deliv- 
 ery of the stream seems to have been reached about 12 M., 
 August 8th, the observations showing very little variation after 
 that hour. 
 
fii a|t[)lyiii r tlio Inriniilas for calciilarn I liavc considered 
 that neither weir followed precisely tlic conditions of construction 
 required in the correct use of any of the ordinary forms. I have, 
 therefore, adopted one most applicalde to bot.li weirs, correcting 
 thi'ni by a moan coefiivient suited more particulai-ly to each 
 case. 
 
 In Ctistel's experiments, at Toulouse, a sluice feet long 
 
 and '2y*oVo ^^^^ wide was used, autl a \\v\r of etpial width placed 
 at the lower end, with a deplh, from the crest of the over-fall to 
 the ])ottom of the sluice-way, of ft. Witli a head <.f 
 
 ft., or a little less than one half the lieight of the over-fall bar, he 
 ol)tained a coefficient 0.602; and, upon either increasing or 
 diminishing this head, very little variation followed. 
 
 The circumstances of this experiment are so closely analogous 
 to our own case at Watts' Pond, that 1 have adopted the coeffi- 
 cient so obtained, and applied it in the formula, 
 
 Q=^.Soj)imy/ll'; where 
 
 (^:=Quantity, in cul)ic feet, discharged per second. 
 
 5 .35 = J ^/f/ h = Thcoret i cal d ischa rgc . 
 
 /=Width of \Vcir = 3,V^^5 ft. 
 
 m = Correction for discharge=0.665. 
 
 At Valley -Sti-eam luvservoir I have used the same form, but 
 / in this case =7 ft., and iii=OA\00 (wITu-h includes err(u* for con- 
 traction). This valu(^ of///, is dcii\cd fmm the results of Biack- 
 welTs iiivestigatinns <ni the Avmi (anal. The width (.(' his wi'ir 
 was (» f('rt,()Ui' (twii bciiiif 7 feet. In his case, the dcjUli of water, 
 for sonu- little distance hack from the o\(M--lall, was reduced to 
 
 18@20 inches, by a suhmerged course of nuisonry. In our own 
 9 
 
we have a corresponding depth of from 13@18 inches for a dis- 
 tance of 4' 0" back. He phiced his over-fall on the outer line of 
 the dam ; the position of our own is the same. 
 
 In case closer accuracy is essential, from the data now in our 
 possession new coefficients could be calculated for each variable 
 head ; the same relative difference, however, would be preserved 
 in the flow at both points, — which I have regarded as the more 
 special object of our investigations. 
 
 The circumstances under which the gaugings here presented 
 were made have been so favorable that I feel great confidence in 
 offering them to you as reliable and sufficient. 
 
 Very faithfully, 
 
 THEODORE WESTON. 
 
 Jas. p. Kirkwood, Esq., 
 
 Ch. Emir. B. W. W. 
 
G3 
 
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 Obseryatioxs ox the Specific Gravity of Water aloxo the 
 
 SHORE OF Ja^EAICA BaY. 
 
 Green's Standard Hydrometer vsed. Distilled Water at C0° Fahr. = 1000. 
 
 DATE. 
 
 LOCALITY. 
 
 jiign 
 Tide. 
 
 Ebb 
 Tide. 
 
 Tow 
 Tide. 
 
 Flood 
 Tide. 
 
 Tempera- 
 ture of 
 Water. 
 
 Wind. 
 
 
 
 1860. 
 
 
 
 
 
 
 
 
 
 
 Sept. 24. 
 
 Mouth of Jamaica Creek (at D on map). . . 
 
 1016 
 
 1014 
 
 
 
 >-oO 
 ( O 
 
 S. E. 
 
 " 25. 
 
 
 1017 
 
 1012 
 
 
 
 bo 
 
 N.W. 
 
 " 26. 
 
 
 
 1010 
 
 10035 
 
 
 0.:5 
 
 Calm. 
 
 " 27. 
 
 
 
 1015 
 
 
 1013 
 
 
 
 Sept. 24. 
 
 About 90(» feet fi-om mouth (at C on map). 
 
 << (i a 
 
 1015 
 
 1014 
 
 
 
 /TOO 
 
 / o 
 
 S. E. 
 
 " 25. 
 
 
 1010 
 
 
 
 DO 
 
 N.W. 
 
 " 26 
 
 <( i( <( 
 
 
 
 1001 
 
 
 Do 
 
 Calm. 
 
 " 27. 
 
 << (( <i 
 
 
 
 
 1007 
 
 OV 
 
 
 Sept. 24. 
 
 
 1016 
 
 
 
 
 iv 
 
 S. E. 
 
 " 25. 
 
 
 
 1006 
 
 
 
 uo 
 
 N.AV. 
 
 " 26 
 
 
 
 
 1000} 
 
 
 DO 
 
 Calm. 
 
 " 27. 
 
 
 
 1008 
 
 
 1003^ 
 
 nQ° 
 OxJ 
 
 
 , Sept. 24. 
 
 
 1014 
 
 
 
 
 i 6 
 
 S. E. 
 
 " 25. 
 
 
 
 1008 
 
 
 
 bo 
 
 N.W. 
 
 " 26. 
 
 
 
 
 1002^ 
 
 1000 
 
 
 DO 
 
 Calm. 
 
 " 27. 
 
 " " 
 
 
 1005^ 
 
 
 1003i 
 
 
 " 
 
 Sept. 24. 
 
 
 1017 
 
 
 
 
 70° 
 
 S. E. 
 
 \ " 25 
 
 
 1018 
 
 
 
 70° 
 
 N.W. 
 
 i " 26. 
 
 " " 
 
 
 1017 
 
 
 
 63° 
 
 Calm. 
 
 i " 27. 
 
 
 
 
 101 Si 
 
 62° 
 
 
 Sept. 24. 
 
 Mouth of Spi'ingfielil Creek (at F on map). 
 
 lol4i 
 
 
 
 73° 
 
 S. E. 
 
 " 25. 
 
 (( t( a 
 
 
 1016 
 
 
 
 69° 
 
 N. W. 
 
 " 26! 
 
 
 
 
 1012 
 
 
 69° 
 
 Calm. 
 
 > " 27. 
 
 
 
 
 1009 
 
 
 69° 
 
 
 Sept. 24. 
 
 Moutli of Long XtH'k Creek (at G on map). 
 
 1017 
 
 
 
 
 
 S. E. 
 
 " 2.5. 
 
 
 
 1017 
 
 
 
 
 N.W. 
 
 " 26. 
 
 
 
 
 1015 
 
 
 
 Calm. 
 
 Sept. 26. 
 
 
 
 1017 
 
 1015 
 
 
 
 
 
 
 
 1017 
 
 1016 
 
 
 
 
 Sept. 27. 
 
 
 
 1019 
 
 
 
 64° 
 
 
 
 
 
 1020 
 
 
 
 64° 
 
 
 '( <i 
 
 " " opposite Sea-siJe House. 
 
 
 10204 
 
 
 
 63° 
 
 u 
 
 i» It 
 
 
 
 
 1020 
 
 1020 
 
 62° 
 
 
 (< <t 
 
 
 
 
 
 1019 
 
 62° 
 
 
 
 Sea v'<(Ur from outside Rockaway Beach. . . 
 
 
 
 1025 
 
 1025 
 
 67° 
 
 
 26 
 
 Water from Salt Creek, running into main 
 
 
 
 
 
 
 
 1 
 
 
 
 
 1017 
 
 
 66° 
 
 
 WEATHER. 
 
 Sept. 24.— WinJy from the S. E. 
 " 25.— " " N.W. 
 
 " 26.— Calm. Unusually low tide in Bay, at llh. 30m. A. M. 
 " 27.— " Usual low water at 12 M.'