Sessional papers of the Dominion of Canada 1911 . In all cases when a first mea-surement is made, it is advisable to establish the depth at which the mean currentoccurs below the surface. It is then possible to determine the velocity by a singleobservation at each vertical during all future measurements in open water; the pres-ence of ice makes necessary special operations. Deep and wide ).—If the river is too wide or too swift, or if for any otherreason, it is found impracticable to stretch a cable across, distances are fixed by triangu-Jation. The length of the should be at least
Sessional papers of the Dominion of Canada 1911 . In all cases when a first mea-surement is made, it is advisable to establish the depth at which the mean currentoccurs below the surface. It is then possible to determine the velocity by a singleobservation at each vertical during all future measurements in open water; the pres-ence of ice makes necessary special operations. Deep and wide ).—If the river is too wide or too swift, or if for any otherreason, it is found impracticable to stretch a cable across, distances are fixed by triangu-Jation. The length of the should be at least J the width of the stream. Rangepoles are set up on the shore, in line with the chosen metering section, and the boat isheld in position on this range by anchors. A transit or is used for triangu-lating the distances. For this method of work, a party of from four to seven men isrequired to handle the oars, and the bow and stern anchors, the number depending ontiie swiftness of the current. 19a—3J V3S 3A(fflV 133J Nl SNOIiV^3^^. W?e lAOBV i33J Nl SNOlVAJla K-J = w^« i t^, fNea —r—^— M f^ ^ i \ \ • •AZflf — \ -^ \ \t :?;; —?- —M CO i 3 t 1 3 -4 c3 3 8 -^ -A ? t gsHg* I i J 1 i f %6- K 1 t MONT OB 8SSE AVER ii \, Jf u £ ^ / i g 1 »s// - ^ 1 ^ ! 1 ? ^ -i / § ? X CO , [_ 1 1 ?v tZtB •-- ^ / w t A .^ fm ^ 5S -«?. R V ^ /- ??? 31 )/ if 4 ?!?? / iW ..».,-.,«« y / /., :?-?:::? )3aj Ul 3|C3S 38 DElAlirMEyr OF ilULlC ^\•ORKS 1 GEORGE v., A. 1911 Shalloiv-irading.—At a wmling- station, where the water is shallow enough topermit of the recorder wading across, the meter is attached to brass rods. These aredivided into feet and tenths, and the current meter can be raised or lowered on the rodas required. A recorder and one man are sufficient to carry on
Size: 1135px × 2202px
Photo credit: © The Reading Room / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookauthorcanadapa, bookcentury1800, bookdecade1860, bookyear1868
