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SCIENTIFIC.
SCIENTIFIC.
The Review company lately presented the Engineering department Vol. 1 of Pallisers' "Useful Details," for which the department is very grateful. This adds greatly to the already large number of drawings which this department has.
One of the latest things of interest to the Engineering student in Lawrence is the "Lawson. Cash Railway," used in L. O. McIntire & Co.'s dry goods house. This system does away entirely with cash boys, and has many advantages to the shoppers and salesmen, as well as to the merchant, over the old system. It may be briefly described as a series of elevated railways suspended from the ceiling in lines radiating from a central cashier's stand to different parts of the store. There are two tracks in each line, one of which is inclined toward the cashier's desk, the other inclined in an opposite direction. The cash and check are placed in a hollow ball and by means of an elevator is put on an upper track; it then goes to the cashier, who puts the correct change in the ball and places it on the lower track. The ball then rolls to its starting point, and never mistakes the place, although half a dozen balls may be on a track at once.
WILL ELECTRICITY TAKE THE PLACE OF STEAM?
Of late nearly all lines of investigation have been abandoned for the researches in electricity, and many talk as if in a few years we shall look back upon the age devoid of electricity as but one step removed from barbarism.
Certainly electricity is of great value in
many ways, but does it justify such great expectations? Will it ever take the place of steam? There have been other things of which great expectations were had, but of which very little ever came; for instance, compressed air. One of the principal advantages which is claimed for electricity is that accumulators may be charged at any convenient place, where for instance a head of water may be used to run a generator and then be conveyed to the place where it is to be used. Compressed air can be much more simply stored in this same way, and is fully as effective. In fact, it has been done and proven a success, but practically it don't pay and is never used.
There are two ways of generating electrical energies; the one by a battery, the other by a dynamo.
Electro prime movers with a battery as their source of power can never successfully compete in power and economy with the steam engine. The reason of this is given in the mechanical theory of heat. The work of these motors is another form of heat which is produced by the decomposition of the zinc of the battery, and it is simply reduced to this—which is the cheaper fuel, coal or zinc? Coal is worth about $5. per ton, zinc about $360. per ton. In the dynamos it is established by repeated experiment that not more than from 36 to 50 per cent. of the energy expended on the generator can be reproduced by the motor; that is, if you take a 12-horse-power engine to run your generator, you cannot possibly get more than 6-horse-power work from your motors.
M. Depres was invited to conduct the experiment of the transmission of power by