471. The Perpetual Calendar.—A calendar which will show on what day or month any event fell or will fall for all time.
472. The Lightning Adder.—It is possible by a system of keys to invent a machine which will set down almost as quick as lightning the sum of any column of figures, thus dispensing with much of the service of a bookkeeper.
473. Copyholder.—Typewritists want a copyholder capable of being adjusted to any size of manuscript and which can be sold as low as twenty-five cents.
474. Envelope Moistener and Sealer.—Construct a narrow brass or iron plate, one-fourth of an inch wide and shaped like the flap of an envelope. A shallow vessel of water is placed underneath, into which by the manipulation of a screw, the plate is occasionally dipped. Above the plate is fixed a second plate which acts as a sealer, and which operates with a screw-head.
475. Multiple Lock.—A device for locking with one movement all the drawers in a desk or bureau.
476. Office Door Indicator.—One to be operated instantly and easily, showing that the occupant is out, and with a dial face to indicate when he expects to return.
477. Automatic Ticket Seller.—It is entirely feasible to have an automatic ticket seller which will both date and deliver tickets. A machine of this kind has been fixed in the Hammerton Station at North London, and is said to work satisfactorily. But there is room for improvement on the part of brainy inventors.
478. Perforated Stamp.—The chief of the London Stamp office said the government was losing $500,000 a year through the dishonest practice of removing stamps from official papers and using them again; and he offered a large sum or a life office at $4,000 a year to any one who would invent a stamp which could not be counterfeited.
Section 10. Money in the Packing Room.
479. Nonrefillable Bottle.—Such a bottle is an absolute necessity to beer and liquor manufacturers, sauce and patent medicine makers, yet no one has yet supplied the demand. Here is a chance, and there are millions in it.