. The street railway review . we con-sider the results achieved both as to efficiency and sim-plicity of working, we see that this complication is moreapparent than real. For efficiency an example will showit better. Suppose we have to deliver current to a motor andmust be able to get 1,000 horse-power out of the shaft ofthe motor, and this current is to be transmitted from a (^|j{cd/9\ailw^j^eA^^ 141 generating station utilizing water-power. Let us see ifit is more advantageous to use multiphase or continuouscurrents for this transmission. Starting with the tirst-named, the efficiency of them
. The street railway review . we con-sider the results achieved both as to efficiency and sim-plicity of working, we see that this complication is moreapparent than real. For efficiency an example will showit better. Suppose we have to deliver current to a motor andmust be able to get 1,000 horse-power out of the shaft ofthe motor, and this current is to be transmitted from a (^|j{cd/9\ailw^j^eA^^ 141 generating station utilizing water-power. Let us see ifit is more advantageous to use multiphase or continuouscurrents for this transmission. Starting with the tirst-named, the efficiency of themotors of large power, either continuous or multiphased,may be taken as 92 per cent, the efficiency of transform-ers 95 per cent, that of the line in both cases 90 per cent,and that of the generators also 92 per cent. So thehorse-power required from the turbines will be in thecase of multiphase currents 1,000 ~ ( x >^ ;^ X 0-92) = 1,454 horse-power. With continuous currents and a transmission in series,. 1300-VOLT (iKNERATOR, IACCINATTI STATION. allowing us to reach the same voltage as with multiphasecurrents, the efficiency is the same for motor, line andgenerator, but we dispense with transformers, so that inthis case, the energy required from the prime movercomes to iooo-f-( X ) = 1,312 horse-power. So we realize a saving of 140 horse-power and theworking is much simpler. SOME PRACTICAL EXAMPLES. After a perusal of the above, it will be interesting toinvestigate the manner in which this company has demon-strated their theory as to direct current transmission. On the side of the mountain, opposite Genoa, is anavailable waterfall of nearly 1,200 feet. This is utilizedby three stations, one above the other, the object beingto obviate using such enormous pressure with the tur-bines. Evidently Pelton wheels are not common in thatregion. The power transmitted from these stations isabout 1,000 horse-power. The highest is known as theGalvani stati
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