. The Street railway journal . d for the construction of 23,000 cu,yards of masonry. The excavation and delivery of ma-,terials for this work have been accomplished by an aerial WATER POWER PLANT The company, after an ex-tended investigation of allwater powers available, finallyacquired the somewhat famousCachoeira do Inferno (Rapidsof Hell) in the Tiete River, atParnahyba. Why the earlyPortuguese settlers gave therapids that name is not known,for they do not seem to deservesuch a harsh description, asthey have practically nothingmore than a uniform dip of 38ft. in the river channel, in length
. The Street railway journal . d for the construction of 23,000 cu,yards of masonry. The excavation and delivery of ma-,terials for this work have been accomplished by an aerial WATER POWER PLANT The company, after an ex-tended investigation of allwater powers available, finallyacquired the somewhat famousCachoeira do Inferno (Rapidsof Hell) in the Tiete River, atParnahyba. Why the earlyPortuguese settlers gave therapids that name is not known,for they do not seem to deservesuch a harsh description, asthey have practically nothingmore than a uniform dip of 38ft. in the river channel, in length of about 2400 ft. The catchment basin abovethe rapids has been well surveyed by the GeologicalDepartment of the Brazilian Government, and .^howsan area of approximately 2700 sq. miles. Records of theaverage rainfall over this basin for ten years indicate anaverage precipitation of 65 ins., varying from 2 ins. to 12ins. per month. The total absence of periods of drouth andthe dense uncultivated vegetation combine to produce an. VIEW OF MAIN DAM, SHOWING PIPE LINE AND WATER PASSING THROUGH SLUICE GATES cableway over the dam. The cableway has a span of 860ft. and a carrying capacity of 10 tons at the rate of 600 minute. An interesting feature in the construction ofthis dam was the design of cofferdam used. The bed i^ockwas always found overlaid with many boulders of varyingsize. The use of timber construction was not feasibleowing to the irregularity of the bottom and the great ex-pense of timber in Brazil. The dams were therefore made 274 STREET RAILWAY JOURNAL. [Vol. XVIIL No. io. by first filling the crossing with stone averaging a cubicfoot in size. A typical cross section for a dam to resist,say i8 ft. of pressure, was constructed with the top of thestone approximately i8 ft. wide, the stone taking the slopenatural to its being dumped into the water. The up-streamside was then faced with a layer of fine brush and heavygrass to a depth of 2 ft. or 3 ft., over which was
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