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 ADVANCE PROOF— (Sttfi/at to lejusivn). 
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 (•'auadiau iroriftii uf tfiiil cMuunfrrs. 
 
 INCOUroKATKI) ISHT. 
 
 TRANSACTIONS. 
 
 N'.H.— ThisSonicty, as a b(nly, (iocs not hnhl itMclf rcKpoiisihk' for tlic facts hihI oiiinicins 
 stutiMl in any of its publiratinnw. 
 
 THE HSQriMAJ/r (il{AVIN(i IKK'K \\(UiKS. milTISlI 
 
 coLrMniA. 
 
 By W, Bk.wktt. .M. Can. Sue. C.lv 
 
 Tn hn read on jlli <■.) March. -^Hlh or Apr!/ \Uli. 
 Tlu'sf works, wliioli \w\\' fully illustriu . in ' I'liiiiiiu'orini; ' nt' tin 
 2t;tli uiiil 27tli of July, 1888. wviv (irifiiiiiilly lojiimoiiccd by the Oov- 
 criiiiii'iit iif Hi-itisli CiihiuiM;!. mill liiivc been cimiiili'tcil at tlic cost of 
 tlic l>(iii)iiiiiiM III' t'aimila, the liiipiTial (iovrniiiu'iit rmitributini; .toO,- 
 00(1 tlicnto, in L'onsidcratiiiii of whicli, any nf H.M. ships havo priority 
 of i-ntvy ami froc ilofkajit^ for ir)yoai's. on payment of workini; cxpi'iisi's 
 only. 'I'Ik' woi'ks wore ilcsiuncd by Mr. Ivinipplc, tlir senior nn'm+irr 
 of till' Into linn of Kinipplo iV .Morris. Kniiinccrs in Cliicf for tin' wliolc 
 of till' works, 
 
 Tlic oiiti'r or Cottonlani works wen' commi'niH'il in Scptc'inber, 187fi, 
 and till' inner or Duck works some four years later. The Karl of 
 I'lifterin. then flovernor (U'lieral of Canada, was present wlien the first 
 pile of the dam was driven. The Doek was opened on liOth July, 
 1887, II. .M.S. "Cormorant ■■ beinu the lirst to enter, and followed, 
 when her repairs were completed, liy II. .M.S. " Cnroline. " 
 
 The pro'iress oi'the outer works was to a certain extent hindered by 
 the fact that at I'lsijuimalt the ranjre of tide, •.vhicli was se.ppo.s.'d to be 
 about 10 feet, is very uiieertaiu, the tide remaining; fri'i|Uenlly at almost 
 II. \V, level for days tojiefher, which tints prevenled the wales and struts 
 of the dam beinu placed in their respectivi' iiosilioiis. The oriL'inal 
 drawings bad therefore to be somewhat nioililied in order to prevent 
 further delays in the completion of this ponion of the work. 
 
 In January, ISTO. tlie contract for the ColVenlam was -iven to 
 .Me.S'^rs. IJeed Brothers, of Tokenlimise Yard. I<ondon, by the British 
 Colundiian (iovennuent. for the >iiin of ,C12,;!1 1. Owim;, however, 
 to the noii-fullihneiil of their contract in the sjieciHei' and extended 
 time, the (iovernment, in dune. 1S7II, after the contractors bad cea.'-ed 
 work altimi'iher. took poissessioii nl'tlie Cofferdam works, and eomiileted 
 them in the followinj;' October, under the Miperintendence of their Kesi- 
 dent Engineer. (I''i'.;s. 1 to 8.) 
 
 When the water was pumped out from the aiea on which the (JraviiiL' 
 Dock w,is to be con>tructeil, the dam was found to be perfectly tiiiht in 
 every respect, altbouiih tor fully om'-third of its total leni;th, of upwards 
 of ')IM feet, vi/.,. at the shoi'e ends, the slu'ct in'.;- piles bad lo be planted 
 on a very uneven fouiidalion of rock, overlaid with sand, .shells, and 
 boulders, all of wliieli. ofeniirs", bad lo be renioveil. ''^iinie of the holes 
 for the rock pile shoes were drilled in 2') feet of water. The dam did 
 mit show the slightest strain when the full pressure, due to a head of 
 nearly ISO feel, was broiiiiht a'.iainst it, and remaineil intact until it was 
 
 removed on the cmipletii f the Dock In |SS7. . Villi, inj;h the ilaili 
 
 was not removed for V y '.irs after its eoinpletion. no pnmpini;' whatever 
 
 was reipiirediliiriii'.; that liinc bey 1 ihal wliieb was due m )iercol;itioii 
 
 through the strata, or to rainfall, 
 
 The three sluices ihroic^h the t'oU'erdani w.'iv noi coiistructeil as 
 
 shown oil l''|-s. ,"). 7. ,,ii,| ,s as niiii'l .iccoiinl of the li'lal difficulties 
 
 alrea'ly referred to as for the avoidaiiee of leakaiic, and in lieu thereof 
 one sluice, ei|nal in capacity to llic three proposed, was built in the 
 channel way at the back of Thetis Islaml ( l''i,^. 1 ), und by its means 
 the Dock was llooiied at the trsrinu of the caisson ajiaiust tbe uieeliin; 
 I'uccs. 
 
 The (.'real er poriion oi'the I'e'llainl eeiiieiit n.sed in 
 
 of the Dm 
 
 K was sup p 
 
 I lie i-iiMSl I ocuo 
 
 1 by .^les-rs. (Jibbsi^ Co.. of (iray's Hsse.v. am 
 
the vomainder by ..lesars. Robins & Co., and otlior well known Eiijish 
 luitkei-H. 
 
 InJinif, 1S75, tfiiilcrs wito i.idoml U, W obtained for tiie Dock 
 punipin.,' niiifiiiiu'iy. and Messrs. .lam.s AVatt & Co., of Sola., JJirniinK- 
 haui, .seoiireil the work at the coutraet price of .itdliOO. 'I'liis eoiitruct 
 ineiuded tlie hoih-rn, enj^ines, caisson huuliiif; nvar, sluices, jmnip.s, &e. 
 The boilers (3 in niindier, one spare) are of the eylindriea! and nniiti- 
 tuhuliir type, eaeh 15 leet hiiiu. and Ci feet in dianiet.'r, having; 2 flues 
 4 feet (i iiuiies leiiji, 2 feet :i indies in diameter, a lar<,re combu.ttiou 
 chamber, and 120 tubes 2* inches in diameter, 5 feet in leof^th. (Fii;. 
 27). The boilers were tested to 120 lbs. per S(|uure inch, tlie workii^ 
 pressure bein- estimated at (iO lbs. The main }>umpinn eufiiues are 
 capable of raising ilOi.OOO eubie feet of water in hour.s, with an ex- 
 treme lift of 35 feet, and a mean lift of 17 feet C inches These engines 
 are of the low pressure eondensiui; liorizontal description. 'I'he evlin- 
 ders, 2 in number, are 27A inches In diameter, with a strok.' of 4 teet. 
 The main pumps are 4 feet in diameter, and 5 feet stroke, the workmg 
 barrels (Fij:. 24) of which are lined with brass; the pump hiicketsa-e also 
 of brass, with india-rubber valves, and desijiued to .li,«eliar-e from 15.000 
 to 18,000 srallons per minute. The auxiliary .iiiiine is ef the vertical 
 direct aetini;- descrijition. havini; a eylinder 14 inches diameter, and a 
 12 inch str.ike. This , 'limine is used both for workins>' the au.xiliary 
 pumps and the cai.sson liaulhiiij;ear. The auxiliary or drainai;-.' pumps, 
 2 in number. 10 inches in diumeter. with a 2i feet stroke, : re jointly 
 capable of raisiiej tiOO to 800 oulhais per minut^.. 50 feet hi"h fFi"- 
 
 2t;.) •" ■ ^ '■■ 
 
 The whole of this machinery was doliverod at Ks((uimalt in 1 87(1. and 
 stored, with the exception of the auxiliary pump, which was used to 
 pumi) out the ar.^a b,.|iind the Corterdam. and also to keep d(.wn the 
 surface draina-e .lurin- the whole jjcriod that the works were under 
 construction ; thus the necessity of obtaininu special pumps f„r this 
 purpose was obviated. 
 
 On the 5th (.f September. 1879, tenders were adv-rtised Ibr tli.- main 
 works, and Messrs. F. B. MeNamee .^ <'„.. Montreal, were the success- 
 ful contraetDis, 
 
 The works, however, were not commenced before the l.-^llKif Septem- 
 ber, 1880; but progress was .slow, and in April. 1882. the contractors 
 stopped work, and conse,|Uentiy. in June, 1882. p...s.s,.ssion of the works 
 was taken by flie (ieveniment .if Jiritish Cdlumhia. The works were 
 carried on fer the following 12 months by day li.lmr. and auain nmler 
 the direction of their Hesiilent Kniiineer, ( )n the 21th uf Auiiust. 188;{ 
 the works were handed .,ver by the Guvernment „f IJritish Columbia t.! 
 the Dominien Uovernm..nt, under the terms .,f the Settlement Bill one 
 ef the terms of which Act i,rovided fin' the r.paymcnt of all sums ,.x- 
 pended on Dock aeconnt by the Federal to the I'rorincial (Joverninent 
 
 J be Demnnon (;overnment tlnreup idverfised for tenders fore - 
 
 pletion of th.. works, but it was not until .N'oivmlMi-, 1S8| that the 
 tender of the w,.ll-kMown firm of Messrs. Larkin, Cninolly -t Co of 
 Quebec, was accepted, and they afterwards proseeiited tli,. works to 
 completion with great energy and ability. 
 
 The Dock is 450 feet in length (Fig.' !l) from the inner face of the 
 caisson, when in its ordinary berth, to the base of the circular head 
 and has a width at the entrance of (55 feet. (Fig 10 ) ' 
 
 The walls of the Dock are parallel for tl... entire len-th and tli,. 
 Width across the floor is 41 feet. The top inside width of the Doek d 
 coping level is i)0 feet, and the depth on ,i|| at ordinary H,W is '>ii^ 
 feet, occasionally, how.-ver, the tiile risis from 2% to U feet hhdier " '" 
 
 The excavation for the Dock, which was commenced in 1,880 was 
 mostly in sand and .shells for a ,lei,th of about .'! feet over the .M.tire 
 area of Theti.s-Cove. B,.low this level vry stiff br.,wn and bin., clay 
 was encountered (with occasional boulders imU'dded). with the exception 
 of an out-cropping of rock, which occurred ab.mt half way ui, the 
 Dock, continuing to the end. and under the cais.son .hamher and engine 
 house foundations. 
 
 The wh(,le of the foundations of the ,•, trance works ar,. of .rlluh.r 
 brickwork, laid in 3 t., 1 Portland cement compo, and the pockets filled 
 in with onnereto. 
 
The walk and Dock ontranco arc 7 to 1 ruliblo concrete, faced with 
 HandNtoni! in li feet courscH. The Handstone laoiiif; of the IJock, aecord- 
 in>; to tlie coiitract drawinjr, was in 1 loot courses ; hut as ^ood stone 
 was easily obtainable of lar^e size in .lie district, it was ultimately 
 decided to adopt 1' feet courses. Tlu! sandstone was obtained from 
 Salt Spriiij; or Admiralty Island, and the uranite from Nelson Island, 
 respectively distant froui Ksiiuiinah, 5(» and 100 miles. A skin of 9 
 inches in tliiekne.ss of 5 to 1 l*oitlau<l cement fine concrete was intro- 
 duced into the bottom nf the whole of the foundations, ajiainst the 
 bucks of all the walls, and also behind the brickwork and stone facing 
 work, and wnerally throiiL'hout the works. 
 
 'J'he whole oi' tlu' Doek-slih' walls are built vertical, the upper poi- 
 tions hiMuj; carried by ruhbh' ciinerete arches. Under the bottom of 
 the Dock there are (i arterial bo.\ drains, laid in 5 to 1 Portland cement 
 porous concrete, which are connected with the rubhle drains running 
 behind the walls in each arched recess^ the whole of which discharge 
 into the drainage |mnip well. 
 
 The inv.rts are ll;i feet radius, the outer being 16 feet wide, and 
 the inner 20 feet, both of which are faced with .sandstone with a heart- 
 ing of brickwork and 7 to 1 concrete. (Fi^s. 10, 11.; The caiH.sou 
 berth meetinu' faces and ((iioins of the Invert are of f^ranite, which are 
 very fine-axe dressed for 12 inches in width, and which have a projec- 
 tion of ^ of an inch. (B'ig, 10.) 
 
 The invert at the bottom of the caLsson chandjcr is of brickwork set 
 in 3 to 1 Portland cement compo. and founded on 7 to 1 concrete, and 
 the walls of the chandjcr are of hainmer-ure,s.scd sandstone, in 2 feet 
 courses, with 5 arched recesses on each side. The chamber is provided 
 with stop .|Uoins (Figs. 18 f 17) at its entrance, and by means of 
 balks of timber inserted therein, can be converted into a dock for paint- 
 ing or rcjiairini; the (;ai.sson. 
 
 'I'he cast-iron boxes currying the rollers on which the caisson travels 
 are set in brickwork on the hottcn of the chamber ;.nd berth. A* each 
 end of the caisson cbamber jiathway there is a scouring culvert, which 
 can be used, when desired, to clear the roller pathway of any mud that 
 niay accumulate. (Fig. 10.) 
 
 The Dock is provided with four timber slides and stairs, of finely 
 dre.s.sed masonry, two at the bead and two at the stern, there are also 
 twelve cedar double fenders, with ladders in them of 4 feet in width 
 six patent hand (lower capstans, and the necessary mooring posts a 
 powder magazine, all necessary lavatories, &c., 3 hydrants on each side 
 of the Dock, with a first-rate water supply. Outside the entrance to 
 the Dock are two wrought-iron buoys attached to screw moorings by a 
 2| inch stud cable, for the purpo.se of facilitating the docking and 
 unddekin;; of vessels. The works are now lit up at night by electricity. 
 The .•ni;ine and boiler house and chimney shaft are faced with ham- 
 mered dressed ashlar, backed with brickwork in Portland cement. 
 The ehimney shaft is ill) leet !l iiiehes above :-oping level ; it was fouud 
 neeessaiy to go to 45 feet below coping for fimndation for the same. 
 
 The paving at the centre portion of the Dock bottom, for a width of 
 10 feet, consi.sts of two courses of stone 2 feet in depth and 1 foot 9 
 inches in width, and filled in between with 5 courses of 18 inches in 
 depth, and the remainiu'j; portion of the Dock bottom is paved with 
 20 cour.ses of stone 2 ieet in depth by 18 inches in width, the whole 
 being laid in Portland cement compo. 
 
 The discharge pipe from the auxiliary drainage pump is carried 
 through the (|uays. and across the caisson chamber immediately under- 
 the surface of the quays, and down the face of the Harbour quay 
 wall. 
 
 There arc also two culvert mouths, 4 feet in diameter, in the faces 
 of the llarlior or (|uay wails. The one on the west side is tlu- dis- 
 charge from the main pumps, and the otiier for scouring the caisson 
 berth at its eastern end. 
 
 One of iMr. Kinipple'.s patented Travelling mi\ Folding Bridge 
 Caissons was eonstrncti'd and ireeted for this Dock, by the Dominion 
 Bridge Works Vo.. at l.aehiiu', Oiicbcc, and transported in pieces by 
 the Canadian Pacific Railway to Ks(juimalt, ThiM-aisson herein illu.s- 
 trated is provided with keels, which travel on two lines of rollers placed 
 on the bottom of the chamber and caisson recess, (Fig. 19.) 
 
Tli(! folding Hiiiluc on tlic tup iil' tlic caiswni is sii)ii)iiit(Ml by livir-- 
 hiiviiii; adjiL-talilr tail W(ii;lil.s. wliirlj fum'tlicr tdriii a parallt'l iniitiini. 
 Till' risini; anil liiwcrin'j nl' llii' |ilalliii-ni ts allrclcil li\ rnllii-s <in llif 
 niisi' III' till' |iiatrni'iii a^ain^l i-iiivril |ilati> jiiarril in tin' almtnirnt. 
 
 The caissiin. wliicli i-^ liaiili'il liy >tiiiin |hi\m r. nia\ lir iliawn in nr 
 out of itx i-i'i'i'ss in Ir.-^s than livr ininiifrs. anil in any wcatliiT. It i 
 ilividi'il iiitii two parts, tlii' lnwcr liiini; an aiitiL'lit oliatiilii'i' orsiifficiriit 
 I'apiu'ity til ii'ilnrr tlic wi'ltrlit of tlir lai.-sipii mi tlic rnllcr^ to a minimuiii. 
 and the upper a tlntatiun clianihcr. rrniii which the water is pMin|ieil unt 
 
 Ir 
 
 ssal'V tu float tl 
 
 ly lucaiis 111 a riilsiinieter whein'Ver it i> neeessal'y 
 
 iiut of its liertli. Alira'^imi of the ineetiiiL; liii-cs of tl 
 
 le caisson 
 
 ic eal^.-on anil 
 
 irranite eill.s ami slop ipioiii> is |irevenleil li\ ilie keels liaviiii; ■'swelN " 
 ill iheiu, as illusli-aleil ( I'lu. -'.'>). which insures a clearaneeiil' all siicli. 
 Ill' nii'i'i'. hi'twceii all tl'" incctiii',;- faces, when the caisson is liciiiL: hauled 
 into or out of its recess. 
 
 The sides of the caisson arc vertical, lull are IicvcIIimI liori/.oiilally, the 
 inner face heiic.: of less width than the outer, in order thai liy iiioviii'^' the 
 cais.siin a shor, distance hack into its chaiiiher. and allowiim the eaisson 
 to float hiuh enmiiih to clear the invert or cill, the caisson may he 
 turned round and floated out. when necessary, for repairs. \e. The 
 
 caLssoii, when afloat. 
 
 he licrthcd auainst the outside iiieetill'j 
 
 face of the outer iiiveil, and hy this means ihr availahl" leiii:th foi 
 dockaL'c would he increased liv ;!1 feet, and the Icic^lh oi' the dock from 
 
 U' inner lace o 
 
 til 
 
 lie 4H1 feet. 
 
 '.V 
 f the caisson to iheliase of ill 
 
 le ciri'ulai' lead would tln'ii 
 
 Hy constructiiiL;' the caisson as above de.scrihed. ll 
 
 haltered 
 
 sides arc dispensed with, and a savintj of ahout I'l feel in width of the 
 entrance is tlierchy ett'ected. 
 
 The caisson is conslriicli'd of a series of hori/.oiital and Vertical 
 aiijile and T irons, with eI■o^s diaiional liraeiiiL; -t feet (> iiiclu's apart. 
 The outside platiun' varies from -\ inch to } iiir-h in ihickness. A tciik 
 ineetini: face or ruhliiiii;' piece 1 foot l> inches wide is attached lo the 
 
 wiiiL; llie vertical sides and 
 
 inside and outside faces of the caisson, li 
 radius of the invert. 
 
 The displac.iiieiit of this caisson is 5:!(l tons, and its entire weiiiht 
 cipials 2!)4 tons, made up as liillo.vs: — Cast iron, (il! tons; brass. 4 
 tons; wroiiLilit iron. liMI tons; teak face and other ironwork. "JS tons; 
 the weiL'ht of the concrete ballast, over 1S(( tons. 
 
 The width of the ri 
 
 fall! 
 
 iil: platliirm i- 
 
 in feet, the heiirllt 
 
 of the caisson from llie inner side of the keels lo ilie eopiiii; level is 1:54 
 leet 111 inches, the leiiiith Il7 feet 2 iiiclies on thi' inner or dock sid;'. 
 and 71 fee' '2 inches on the outer or harbor side. 'I'lie keel blocks are 
 of cast iron, in three pieces. \ved'.;e shap. d. llie lower |iiei'.' is clu'cked 
 into the stone paviiiu. each block is provided willi a Inr 
 cajp and a rubbiicj piece on lop. 
 
 The ilocka'.;e rates are at present as follows: — 
 
 'i< Woinl all! 
 
 (iross Tl 
 
 A Vissc 
 
 Kiir all vessels up lo Hum loiis 
 from lllllll In JUIIIl 
 lilKMI to :!llll(l 
 
 " liiiiin 111 I'lUiiii " 
 
 jForeach follow'): 
 For thi'lirstdav, 'lav, iiicludiii] 
 
 Ml M.l 
 
 the loidoekim; 
 .lav. 
 
 I 8 ion (Ml 10 cenlsper ton. 
 
 I ."lOO 00 S •• 
 
 I lioo 00 i; ■• 
 
 I TOO 00 5 •• " 
 
 It may be of some interest to meniion ilial the almv.' rates aie 
 sli'.;htly less than ihose al Vokohama. .laiiaii. and from 100 to liOO |iir 
 cent, less than those at San l''ranciseo. r.S..\.. should a vessel oecii]iy 
 tin dock from 7 to 10 days. 
 
 The Hoyal Naval Dockyard is adjoining the I iraviici' I lock property, 
 and to the westward thereof, thereby affordiic^ -real facilities for re- 
 pairs to any of Her Ma.jesty's sliiiis, 
 
 The total cost ol' (he (Jravini; I lock Work-, iiielnsi\e ol'llie -lie, the 
 cofferdam works, as well as ibe eiieiiie and boiler liniise,-. piiliipiic; 
 inachiiierv. and eaissoii. aiiio 
 
 Ullted to about UISO.UOO. 
 
 .Mr. William IJennett. 
 
 i! 
 
 M, Inst.C.lv. .M. (' 
 iitil tl 
 
 111. .^oe. 
 
 (Mv. was lie 
 
 It l'".n'.;iiiei'r from ISiii. until the completion ol llie works in 
 
 IKS7. and .Mr. h'raiicis Olieilly was for two years 
 
 IIS assislaiil.