499. Self-Winding Clock.—An arrangement such that when the weight of the clock touches a certain point it will set in operation a mechanism which will wind. The prize for perpetual motion has never yet been awarded. Possibly the solution is in the self-winding clock.
500. Dose Stopper.—A thimble-like contrivance which shall act both as a bottle-stopper and a cup to contain the exact dose.
501. Faucet Measure.—A device for measuring the quantity of liquid that passes through the faucet. Invaluable for store-keepers.
502. Automatic Feeder.—A feeding rack so constructed that the hay or grain will be fed automatically with a cut-off when the proper amount has been given.
503. Coupon Cash Book.—At present persons who pay cash are charged the same as those who trade on credit, a practice which is manifestly wrong. A cash-book should be made so that those who pay immediately for goods should receive a rebate. Every merchant would purchase a quantity of these books, since the great bane of merchandise is bad debts.
504. Gas Detective.—A device to be placed on a gas fixture to ascertain instantly whether it leaks. Often there is an odor of gas when it is difficult to tell whence it proceeds.
505. Paper Towels.—Paper towels having the quality of cloth, yet designed only for a single use, will doubtless be a feature of the near future. They will “make” their first maker.
506. Water Filter.—A cheap device for use in every household, one which could be attached to the water faucet, and which would insure pure water. It would sell enormously.
507. Pneumatic Freight Tube.—If small packages for store and post office use can be sent by tubes, why may not the principle of compressed air be extended so that grain and fruit may be transported thereby, thus saving the great expense of handling and of car freightage? Some day the greater part of our freight will be carried by this means, and he who is first in the field will coin a mint of clean dollars.
508. Storm Warning.—Apply the principle of the barometer to a large glass globe, placed on the top of a public building, by means of which the contained liquid shall be colored red on the approach of a storm; or construct an instrument which will give forth a sound when bad weather is to be feared. Such an invention would be wanted everywhere.