The Timaru Herald. MONDAY, FEBRUARY 19, 1906.

Timaru Herald, Volume LXXXIII, Issue 12906, 19 February 1906, Page 4

The Timaru Herald. MONDAY, FEBRUARY 19, 1906.

HARBOUR DREDGING. From the full report of she engineer s<i the, Lytt<elton Harbour I'o.nd. a copy >jf which has been shown us by Mr Fraser, chairman of the Timaru Board (together with a comment upon it hx Mr Jkiynes. the Board's engineer). we note that tbe I.yttehon hacke" dradge h.M ytar lifted 551.232 cubic yards, or 765,504 tons, of spoil. If the dredge ordered by the Timaru Board could lift as much from the Timaru harbour, taking tbe area at 50

arm--, audi disregarding tie t-.light deposit of fiw4 material going on in «. y«i.r, it ■would ir.ciiea.se tbe depth by 7{fi nil over. Tbe diking of l.yi 1 niton harbour is estimated by the engineer at. 6 inches per annum.. It certainly in not great. «it Timaru; at all -events tie foundings and dredging* 4o not indicate nc» much. A table of dredging don*- a.t Lytt-elton. for 22 Terns give* a total of nearly 5| m£Uiutt cubic yards n-mcved. Allowing for an -isxnual deposit, <-i >ix inches. such an ;:HK»actit of stuff lakm out of I] J<; sinaDer Titiwra barb ur would give a depth of over 80ft ! One year's vcik. ~lJov,h! g !: r a Oq.osit of mx itn-bv ;uj addition of *evea feel. The MmrMMcr 1:;-;t year lifted 76?.503 lons. The two Timaru ■dredges lift'.d 35.965 tor.*. JJ r Uavncs' comment on these figures i* ah * j () ], lows:—'" Those who. 'bad their doom' abtjtit the bucket dredge sbwrld studv Mr Williams' report and note results at I-yt-tdu«—76s,soo tons for the year (double shift). Halve it. and we hav-e 567,750 for single shift of one bucket dredge, as against- 35.960 for our tiro dredges. Deduct again cne-fourth from tbe Lyttelton mult* for the easier material dealt "with, and we Have, in round cumbers, 287,000 tons for one year's work <t£ a bucket dredge in mixed clay, gravel and «and, against 36,000 far two grab and pump drudge*. ij, other words, one bucket dredge <A the Manchenter's capacity ban ooiie eight times as much work as <mr tr, i, dredge* under equal condition*." Just ' r.c criticism suggest* itself in considering tbc engineer s comment, and that is whether one-fourth is a sufficient deduction to make on the Manchester* performance for tbe comparatively easier material jibe has: to deal with. We (should think that the bottom of tbe Timaru harbour is so much harder than that of Lyttelton. tus to justify and require a much larger deduction. The tallies of the Lyttelton dredge are. however, so good as to permit of evtn extravagant allowances being made ■on that ground, and still leave a. large margin in I favour of a, bucket dredge. The cost of tbe Manchester lart year is 'given, as follows (we omit shillings and pence) : Wages. £4851; mal, £1726; repaint and renewal*. £316" (ibis includes £1250 worth of new gear not yet put in); stores, £882; total. £10.626. This total cost works out at 5.15 d per yard, or 3.70 d per ton, including' itserc«; or f1.62d per yard, or 3.33 d per t< n. without interest. It will be admitted that figures of cost per yard or per ton -are tiatisfaetwruly low. and they jhc not the lowest sbo-n-n in the Manchester s history. With one exception tiiey -arc the highest for six year* past, owing to trtja outlay on repairs and renewals. charged as working expenses. In 1903 the cc*t per ton. for a tally of 622,003 tons, was only 2.85 d per ton. exclusive of interest. Yet the Manchester, hays Sir Williams, is defective from an <econofflucal point <>f view. .She has an unnecessarily large cnal consumption, partly due I<l the main tngihes being too large, and partly to minor ca.wes •connected with the use of Mfam. (Tlie Manchester's indicated horse power is 13-00. that of the dredge ordeted for Timaru 900.) Mr Barnes" remark is justified. A study < f Mr Williams" report is calculated to encouiage ibofc ho ""bad their doots " abi.ut the bucktl dredge.