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{All rights reserved.) 
 ADVANCE PHOOF —{Suhjm to revision). 
 This Proof Is sent to you for discussion only, and on the 
 express understanding that It is not to be used for any other 
 purpose whatsoever.— (J>'<f Sf,-. 39 0/ t/u- tcHsiituihit.) 
 
 Canadian Joclfty of CTivil tfuflincns. 
 
 INCOIIPOKATKI) 188T. 
 
 TRANSACTIONS. 
 
 N.B -Thin Siicicty, as » bmly, liora not hold ItHolf n-apoiislblB for the facts aiiidopliilotii 
 atattiil in luiy if ItH imblicHtloiis. 
 
 THE COLOMAh (JOVKHNMRNT' DRV DOCK, ST. JOHN'S, 
 NEWFOUNDLAND. 
 By H. C. BuRCHEM,, M. Can. Soe. K. C. 
 To be nad on ifiotuhn/^Mnri-h 2K!h m- April 11th. 
 Tiu" Dry Dock, which is tliu suhjcct of this Pai)cr, is situated at the 
 Rivcrlitad or \Vc,><tiTii ciiil oftho Imibour of St. John'.-',, 
 
 It is built of wood and cohfivtc The form is illu.struted by accom- 
 panying (Imvinus. anil tlw following ..iv the prineipal dimensious: — 
 Leiiiith upon toji from inside oi' licad to ,i;ate when 
 
 at outer .sill ,;0(, ft 
 
 lienjith u|)on tiu; line of iveel bloeiiinj^ 558 " 
 
 Width u])on top at iiead 78 " (j inch 
 
 body 132 "(J " 
 
 '■ ■' abutments 84 " 9 " 
 
 Bottoin width from inner end of abutment to angles 
 
 noar liead 49 " |q a 
 
 Bottom widtii at abutments 52 " 9 " 
 
 Dejitii of water over uate sill ( H,W. Spriu"' Tides) 25 •' 
 Tile Hoor is founded on a b.'d of Porthind cement, concrete, laid 011 
 exceedingly hard cemented j^ravel (lilaeial drift) innnediately over- 
 lyin>; the bed rock. Bedded in the concrete and held down by fre(|uent 
 aiiciiorstrajisofL'A in, .x ^ in. iron is a sy.stom of longitudinal pitch pine 
 timbers 12 in. s(|uare. Immediately under the keel tn-ck four of these 
 are laid dose together, each anchor-d to the concrete and all bound 
 togetlier by throudi iiolts. Two on each side of the keel track timbers 
 are one foot a])art. and the remainder of the longitudinals from this to 
 the edge of the floor are set with three feet sjtaces. The anchor straps 
 are bolted alternately to oii]iosite sides of the tindiers. and are iield in 
 the concrete by a simple right angle be.ul. 
 
 Cross floor timbers of pitch jiine 14 in. x Ki in. and 4 ft. from centre 
 to centre are laid on and securely fastened cO the longitudinals. Their 
 ends are boxed down to receive a stringer piece 12 in. x 14 in. which runs 
 around the sides and head, and receives part of the thrust from the 
 main braces. 
 
 The concrete extends beyond the floors, and is carried three feet up 
 the sides and head iu'hind the altars. Within the flooi area it fills the 
 spaces between cross floor timbers at their ends, and slopes thence gra- 
 dually to shallow drains formed between the longitudinals, on.' on each 
 side of the keel track. The entire lower .system of floor timbers is 
 eom)iletely embedded in and covered by concrete. 
 
 The working floor is of y in. plank, spiked to the cross timbers with 
 ample opening left at the joints. 
 
 In order to lessen the possibility of water courses, the longitudinal 
 
timbiis lilt' iiiiiittiMl in tlio alntiiiiiit, aud under the finte platform and 
 apron ; liut licrc (In- concrcli', instfad (li'ltcinii as at tlu' head 2J I't. 
 avcrauf dfptli. is (i I'l. dco]) witli ahciior strapH lor tin.' cross Hoor lim- 
 bers extending t(p liic liottoni. 
 
 No indications ^of springs wen? oliscrvcd durinii construction. It 
 was tiiout;iit lu'st, lidwivcr, in view of ]]ossiliic dcvrlopnunts of cither 
 Hpriiiu wati'r or nnil( r h'aka^i'. to insert in the concrete 2 in. vertical 
 iron tnhes. li(( ft. apart, alternatini; on o])p(isitc sides ol'the keel track 
 throuiiliout the lenulli of tile dock. Tiie lower ends, extendinn into 
 the ura\el lielow the coiicrctc. vveri' left opi'U, and tiic upper ends, jiro- 
 trudinu ahove the ce.iK-reti', were litted with valves (lij;ht dead weijihts) 
 vipeiiiii!: upwards. There has heeii no flow from these tidies. 
 
 A line of slicct piliin; siirroiimls the entire structure at a distance of 
 2(i ft. IVom the cojiini:. 'I'he sides ol'the dock are su|i))orted liy trans- 
 verse frames 4 I't. apart from centre to centre, extending from the floor 
 
 to the li f sluct pilinji. and made \\]> as follows : — A heavy piteli 
 
 jiine uiain hrace or rafter aliultini; at its lower end on the cross floor 
 tindicr ami stringer already descrihed, ami at 'Jts upper end on the 
 copinii ; a caji of 1l' in. sipiare pit<li jiiite runninn horizontally I'rom 
 cojiinu to sheet pilini; ; hrace and ca]i restiiii; on 12 in. spruce piles 5 ft. 
 a))art, all three jiarts ol'the system lieiiiu hound toiietlier iiy a diai;onal 
 tie of ])itch pine, tirndy Ixdied (o them, and aetinu. to use another roof 
 term, like an ordinary collar heam. 
 
 These transverse frames are conneeled on to]i hy the copinu, wliivli 
 is built up of three heavy pieces of ]iitch ])iiui, and are farther stift'eiicd 
 laterally hy the altars. The altars are of pitch ]iiiie. Two are sawn 
 from a stick 11 in. x 14 in., hy rippinu ohli(|iiely. not from corner to 
 corner, but euttinj;- each 14 in, side .'• in. hack from the corner. TIh'sc 
 are bolted with an ohli(|iie l'a<i' restini; on the main hraci's, an 1 1 in. 
 side u]i]jermost and horizontal, and a ;i in. side lookini; towards the 
 eopini;. ai'd coverinu hy tliat much the next altar above. A .scrii^s of 
 coutiiuious ste])s. ascemliui; from lUior to co|iinu with S in. ri e and 
 11 ill, tread, is thus formed aiiiiiid the ent-ir<' body ami head of the 
 dock, admittiiin of convenient access at any point. 
 
 The entrance works ditl'er somewhat in detail of construction fr<im 
 the body. Six lines of transverse sheet piline on each side run I'rom 
 the floors to the main outer line before referred to. one at the end of 
 the apron, two at each sill, and one at the inner i-nd of the iiiiiei' 
 abutment. The concrete foundation is carried 5 feet beyond the floors. 
 and the sides or walls are backed by concrcti^ f) t'(!et thick at the bottom 
 and 2 feet thick at copiiu!. The cross floor timbers ami main braces 
 are covered by two thicknisses of (i in. timber brcakinji joint. Each 
 course is thoroimhly caulked with dry jiiiie wedires. 
 
 The tr.iusverse floor timbers in the inner abutment are lU in. hiuher 
 than the rorrespondiiiLi body floor timbeis. The rise from the main 
 floor is formed by six larii-e oak timbers, rabbetted and bolted toutther, 
 and baekeil up by heavy oak i.uees. running; back over and framed into 
 the main floor timbers. 
 
 There are two positioii.s for the jiate 2(( fe(!t apart. At each sill 
 four heavy piejes of oak rabbetted and securely fastincd together form 
 a step or ofl'sei , that runs acniss the floor and n]i ihc siiles. and receives 
 the weifiht and thru.st of the ^ate when in position. The top coiir.scs 
 of 6 in. timber are rabbetted into and ar<' flush with the sill timber. 
 There are no grooves, and the chances of troublesoim? obstructions an^ 
 consequently much lessened. The ofl'sets are fitted with stout rubber 
 gaskets, against which the aate bears and forms i water-tight joint. 
 
 2 
 

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 o 
 
 GCNtRA 
 
 jir.?. 
 
 g^- -JT -'-. - -V - » 
 
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 *i "iiy^i ■r p'^'^-— ~:? 
 
 LOr*oiTXJDI/>tmL 
 
 -INDTMWlSt StCTION or F.NOir^l Houst 
 
 — c 
 
 BOSS OECn 
 
 i 
 
 1 
 
 
 
 *^ 
 
 p^ 
 
 Houst. 
 
GtaiU — 
 
 GCNtBAL Plan;.. 
 
 V 
 
 -■JiftaX. -- -. ---^'^3'.- .- .- 
 
 (ftia-^e V/U. g-jj^M/ 
 
 • • .>»V„Ti''t>»/.V 
 
 ^— . Colon i/iu Gotre/nHMENT Dry Ooch. 
 
 Saint Johns. NtwrouNP>.>»No. ■ 
 
 
 1 
 
 - - •• » 
 
 St '<MJ ■ 
 
 SiCTION C.ft- 
 
 ^■iJ 
 
 —— OtCTItM. tX' 
 
 r j<;^- — ^. -'-'V— 1-1 1 1 jB 
 
 Ikbil 
 
 P . v^-'tll 
 
 JSt. 
 
 — C«055 Section o^ ErjCiNt Housi- 
 
 Cko»» Sic. at C. D. 
 
 Cross Stc. at G.H. 
 
 H 
 
 J — I rrj 
 
 ! 
 
 COLONint. Gore/iNf^t/yT Drv Dock • 
 
 Saint JomnS. NtwrouNOLANa 
 
 Ca 
 
 isacN. 
 
tinilH-rH lire mnittt'd in tlic aluitint'iit, aivl uiu]('r tiif 
 a|ir(iM ; lull lirrc tin' <-<iiit'i-i'li', iiiNlciul riH'iiii.MiN 
 liVfi'iiur ilr|>lli. is {'i It. ili'('|i witli aiii'lii >trit|iH tor 
 berH fxtvnilin^- tn tiic luittoin. 
 
 No iiiiliriitiniis ^lt' s|pi'iiiu.s WfiT (il ivi'd (liir 
 
 WllH tliiiML;lil lirst. liiiwi'ViT, ill view iil |i(is>i|pli' t' 
 hpriiiii wati'i- nr iiiulii- Icakiiiic. to iiiscii in the 
 iron inlio. lilt It. ,i|iart. nlti'i'iiiitini: on o|i|ioNili 
 tlii'oiiLilMMit till' li'ii'^tli of tlic ilock. 'I'iii' low 
 tliL' irnivi'l lii'low ilic I'onciTic, wni' It It n|i('ii, 
 tnnlini; aliovc the ciinrri'ti', wri'i' liitcil witli v 
 oiiriiin^ upwards. Tlirri' has lit'cii no tlnw I 
 
 A line III' slii'i't jiiliii'^ siirnmiids llu' iiilin 
 2ti It. i'i'oln till' ro|iiiiu'. 'I'lii' sides of the di 
 vcrsi' riaiiH's 4 I't. a)iait Ironi rentre to ri iit 
 to the iiiir III' shirt |iiliM^. and niadr u|i 
 ]iiiii' main lirari' or ral'tii' ahiiltin'j at it^ 
 tiiiihi'r and slriiiiii'r already deserilied, ii 
 copiiiL! ; a eaji of I'J in. sijiiaie pileli pi 
 i'o|iini; to shi'i'l pililii; ; liraie and lap ie( 
 ujiart. ail three pails iil'tlie s)'slelii heil 
 tie iil'iiitc'li (lille, tiriidy liolted to tlieiu 
 term, like uii ordinary eollar heam. 
 
 'i'hese transverse I'lames are eoiiii' 
 is built up III' three heavy pii'ei'sol'p' 
 kterally by the altars. The altars 
 from a stick 11 in. x 14 in., by ri( 
 Cdriier, but euttini;' eai'li \l in. side 
 are bolted with an oblii|Ue liiee ri' 
 side upperniiist and hori'/.ontal. ii 
 eopini;. ami I'liveriliu by thai mil 
 Continuous steps, aseeudiiii; Irur 
 11 in. tread, is thus t'ormed an 
 doek. admittiiie of eonvi'iiient • 
 
 Till' entrauee works ilitl'er s 
 the body. (Six lines ol' trans 
 the floors to the main outer 
 the apron, two at each sill, 
 nbutuient. The eoueruti' for 
 and the sides nr walls aro bf 
 and 2 feet thick at eojiiui; 
 aro covered by two tliickp 
 course is thi)ri>imlily caull 
 
 The transverse floor ti' 
 than the correspond in.i; 
 floor is formed by six If 
 and backed up by licav 
 the uiaiii floor timbers. 
 
 There are two pos... 
 four heavy pieces of oak rabbettoii .,.. 
 a step or offset, that runs ucro.ss the floor and up i.. 
 the weifilit and thrust of the uate when in posit inn. The top . 
 of 6 in. timber are rabbetted into and are flush with the sill timber. 
 There are no irrooves. and the chauees of troublesome obstructions are 
 consequently much lessened, Tlie oflsets are litted with stout rubber 
 gaskets, against which the uate bears and forms a water-tijiht joint. 
 
Tilt' apron in oonHtniPtctl nn a pnncrctt'funndiition in Himilnr initniier 
 to tilt' floiii-H ol' the uiiti' philtiiniis. flif tinitMT h*?itif! fovcrt'd \ 'th an 
 t'Xtru liiyiT i>v laciiii; of (■(incrrlc. 'I'lic ii|iniii [iri(|)t'r t-xtenilH -1 I't'et 
 hi yond tin- nutcr i^ill witli ii iiiniTt'tt' Uw fiirrii'tj IM iet-t turtht'r. 
 
 HIiccI pilcM lire iiC s|niict' fiUfil witli dry pinit tnntfui'M or kcyH. 
 Bfiirinu^ pili'H iire of llic •^iinic limber. All uri- drivfii to thf li»rd 
 jiiavcl III) whifli till' foncivti' foiitidiitioiiH of the ttimrn wM, »o thiU thti 
 wlioli' !"tnii'tiiri' hiis a pi'itVclly uiiilniiii hciirinvr. 
 
 Tilt' I'xciivutioM of ill)' dotik liiisiii ttiis nmdf ufttT uiont of thf pilfn 
 hud liiTii diivfii. The iiiatt'i'iul I'Xfuviitfd whh iilluviiiin, hiiviii^ hut a 
 email pnipoition nt^ L'liivrl. and was found to hi- inipfrviouM to water; 
 h«»n€!f nn mort' wa« di«tnrbf<l than wa.t nei;»?s.sury for the Hettiii^ of 
 uniin hiaci's anil tifH. Am tht- alturw were put nn. all exiMtiuff spaces 
 WiTf tilli'il with snitahli' niati'i-ial taki-n from the t-xravatiun. and 
 tlioioiii.|,|y ramnu'd. N'cry siiuhi iudiiMiiou^ of li-aka>;i' uppi'arod at 
 M'Vi'ial points in tlu' piani', dividini; tin- niori' recent from the iflueial 
 ilrift, This was donhtless fiinsfd hy the same plane having been cut 
 in tlred^'inu a wet slip on the South side of the doek, 
 
 The area around the doek was filled with earth carted from the 
 nei'jihtionrini;- hills, and was i^raded level with the top of the coping 
 tiinlier. Cross-caps and sheet |iiles are thus covered hy ahmit two feet 
 of liround. 
 
 The coftei'dani was lorined hy driving three ])arallel rows of sheet 
 jiilin;; iihont "» feet apart, each row ln-ini; re-inl'oreed hy round piles 
 and braces. The intervenine spaces were filled with earth. 
 
 in plan its form was three sides of a rectaiiiile. the two parallel side* 
 b.'inu under tlie piers at eaidi side of the dock entrance, and the third 
 connectinii' them just outside the toe of the apron. 
 
 Till' duck is fitted with slidiiif; biliic blocks, 28 on each side, opera- 
 teil from the copiiio- by endless chains. 
 
 Keel blocks aii' placed on each cross-floor timber. They are thug: 
 4 ft. .qiart from centre to centre. 
 
 Afateriais are sent to the v.'orkin;^ floof by means of six slides eou- 
 veiiiently situated, three on each side of the dock. 
 
 The L'ate is a tioatiii;; iron cai.ssiin. It is provided with a steam 
 capstan, a 10 in. direct actinji ccntrifufjal ballast pump, and a boiler. 
 The capstan stands on the upper or flush deck. The eni^ines that 
 operate it and all the other Httinj;.-. are on a lower dock. 
 
 Eiuht pipes, or tillinn' culverts 22 in. diameter, that pass athwart-ship 
 tliroujrb the i^ate, afford a means of fillin;; tiie dock. Tht!y are fitted 
 with valves controlled by hitiHl-wbeels on the lower deck. 
 
 The fiate is moved into anil out of position by the steam capstan and 
 suitable war])S. Kaisinu- and lonerinjr arc effected by the ballast pump 
 and inlet valves. 
 
 The pumpins; installation is placed in a brick building a little back 
 ol' the iibiitnu'iit on the nortb side. The ]iuin])s anden^'ines were made 
 by \V. II. Allan iV Co.. of London, Ene. There arc two thirty inch 
 centrifugal [lunips, each driven by an independent single engine. The 
 discs are ") ft. (i in. in diameter, with cuivi'd arms similar to the appold. 
 The suction expands from 'M in. to 'Mi in. t\w size of the wrought iron 
 suction pipe. The discharge expands from 30 in. to 48 in., at which size 
 if delivers into a brick culvert 14 ft. (i in. wide, T) ft. 8 in. deep, and 
 GO ft. long. The suction is divided into two passages at the periphery 
 of the pump, and water is drawn into the disc chamber from both sides 
 at the centre. J]ach pump is fitted with a steam ejector for 
 
 3 
 
Tin- I'liKiiu'N un- Hin^:!*'. luirixontal vnriiiM.' cnt-ofl', dinvtly cnnn.'rt.'d to 
 
 th. |>iiia|> shiit'i^. Cvliiidirs mv 21 in .lia (.t, Nliokr, -JL' in. 
 
 Tlir,li,iiii,iHr nml li'aku-r iiiv iviimwd hy a MUli. H.'ald luid Cinpo 
 .•.iitririipil. di-iwii l.\ a pair ..I' v.iiiral rn^Mm.s diivi'tl> .•.iiin..,(,.d. 
 'I'l... I'litjiii.. pit is ......l..s,.,| l.y s|„.w pilii.M. K,„- a r.,i,i„|;iii.,n roiind 
 
 |.il.>w.iv diivii ;tA li. apail, all ^..li nmtoiial \v:i« oxcavalc d to u 
 d.|.(li or:i ft. I,,.|,.w H.H.I- hv.'l, and a .|miiitity ..n..oMi. Mti.ne llii'..v,ii in. 
 
 Th,. pi|,.,s w.T.'.Mpp,.,!, and. ivic laid >,u lli.. I.,..s.. ..t..n.. was lauiin.'d 
 
 '•"i'i"l ""■"' ^'i.d l.n.i.i:!,! up l.v. I will, tl.. eapn. A d„ul.i.' fl„..r ..f 
 .anlL.I :< in. Hprii.'.. Was lli.n lai.l, an,! ai,.,tlKT thickiifHH of iM.mirftf 
 pla..Mi ..n it.. Th,. pumps an,l ..imin.s w.iv h..,l,h..l .,n this iMiin.lation 
 HI .•.....•.VI,. lutT,! will, iMi.k. Tl„- wails. ,r tl... ,.n..in.. I.....,s.. Mm ri„m 
 the xuin.. plair..i>in. tl... .spa... L.tw.,., walls an.l wliwit piliiij; bidnjr Hliud 
 t.» th.' siirrai;.' with .■.i-icri't... 
 
 Th..... ar.. fw.. iM.il.is ,>f ih,. Miaiii... typr hiiilt „r .Si,-.ni.iis-Alait..n 
 Nt.'.!. Th..y ui-.. \2 It. !t in. diaMi..t..r and II It. (i in. l,,,,-. Kadi 
 has Ihr,.,. furnacs :{ ft. i„si.l,. .lian.,.|,.i., S li. ;! i,,. 1,,,,-, ..ach fiiiimvu 
 .Jp.'ninjj int.. a scparat.' ..iiidi.isii.in (.haiiil...i'. 
 
 Thi! c.ntract Htii.ulat...! that th,..,. sh,„d,l h,. pmnpin.^ .•apa..it.v sufti- 
 
 fiontto .n.pty th.- d..fk wh.i. „n.|,pi,.d l,y a I'.ddll ship "in lw.» 
 
 liournamla half. At an „Uioial trial ..nd,.".' .lM.,.,.ti„u ,.r th,. wiit.T th,. 
 d..uk was..ni|.ti...l with.ii.i a .ship in it !,, iw„ h„uT-s ami tw..nty minutes. 
 At .•v..ry six InL.h.'H fall .,f tl... wat...' .,!,; vrvatifms w..r,. lak.n ,.f th,. ,,. 
 Hteum P1-..SSU1... ill boilers, an.l sp,.,.,l „f ..ni:in,.s. The spo.'d of the 
 t.n;.'in,.s, ih..n,t;h slifihily inL.|...asinu, was ...imparatively uniloriu. It so 
 happ..n,.,l „lso that th.. ,l,.ptl, of wat.r was iv,ln..,.d at a unilorin vnU; 
 that is to say. v..fy nearly ll... .s.,„u. tin,,. ,.lap.s,.,| l,etw,.,.|i th,. „l s.'|.' 
 yati.>i,s, from whi.'!. it will app..ar that tl„. slip r..s..ltin.^ fn.m th.; 
 n.en.a.s..,! ,|..pth ,.f s.ietion varies approxi.iiat,.ly a ; tl... eontents ,d' a 
 layer. ir stratum ..f a -iv.'ii ,|,.pth at varying ih.pths in th,' ih.ek. 
 
 On th.. soi.th tide ,,ftli,. ,l,,ek is a w...„h.n IVeiLdif. sh..d 40(1 ft. x HI 
 ft., c.mv..nieiillysil.ial,..l f..r a .-"tora-e ,.f eai-,., ..itiier .'V.-in .ships in the 
 clmnn..l .Ired-.,..! dir,.etly ahin-sid,. or fn.m ships in the doek. 
 
 On the opposite <.r north si.l,. a l.riek huildin-HKI ft. x .'if. ft. aflonls 
 ample si.a.-e for eonv..ni,.nt ollie,. aeeomniodali,.n, stnn.s an.l work-shops 
 The sh..psa.efnrnish..,l with. ■h.et.i,.|i..:ht plant, jiunel. sh.ars. rolU 
 an.l„th..r niaehin,.ry suitable for ivpairs of wo.,,1 ,„„! iron ships and a 
 KtatDiiary enuine niviiiL' the ii..e..ssary motive pow.'r. 
 
 Am.m^r th.. mo.st promin,.nt f..atun.s in this .h.ek are th,. ..nti",. 
 absene.. on th.. w..vki,,i: Ho„r of .lisenmf..rt or ineonv..Mi..n..e from ,lrain- 
 iW; the abundance of liiiht and vntilation for w.n-kmen .....suit m-- 
 from the ^miat top wi.lth ; th.- rea.lin.'ss with whieh shor,.s neiy be 
 .ul,,ust..d, ..win,^ to the small and n,.mrr„„s altars: and the faeiliti..s 
 for .;xpeditioii construction. 
 
 The materials u.sed were tl... very luist of their respective kin.l.s, and 
 the workmanship most ib.ir.mLih thn.niihout. 
 
 Th.. only casualty that occurre.l .Inrinu cnsf ruction was a slhdit 
 movement of the material .,n the .south sid,. of th.. ..nt.anc,. works b..fon. 
 the fram,.s or e,.ncr..t.. were put in. It was promptly .sf„pp,.d bv a 
 «y..t.™ ..f strut.s t., the opposite sid... ami oav no fMrth,."r trouble. 
 
 Thew.irk ..f construction was commene,.d ,,m L'.Sth .May. \SHH and 
 was .suspend,.,! for four months ilurinn- the winter of 1H83-4. Ou the 
 lOth J)ec., 1,S84, the dock was f,n-nmlly ..pened. and H. M. S. " Ten- 
 edos " was successfuly docked.