This Is The Latest and Best Full Swm W-----) ------------ -----------------------------------------------------------------------------‒‒‒‒‒‒‒--------‒‒‒‒‒‒‒---------------------------------- --‒‒‒‒‒‒ Valve Motion Model About as big and heavy as a watch. Made entirely of metal, nickel-plated, with crystal, dust-proof. Shows CORRECT MOVEMENTS of valve and piston, and sections of chest, ports, and cylinder. Can be carried in pocket or will stand up. A real model, with a crank and eccentric-not a toy. It shows lap, lead, cut-off and compression-shows just what a plain slide valve engine does when at work. This model ought to be in the hands of every engineer in America, and can be, for each can have one for himself without costing a cent in money. Fill out slip below, cut it out, and send to POWER, World Bldg., New York, and we will tell you how to get one. ---------------------------------- INVENTIONS-PATENTS (Continued from Page 424) an application as early as possible if the reduction to practice has not already been made in a manner susceptible of clear proof. If the application be filed, the actual construction of a specimen, which sometimes is very expensive, may generally be deferred. If the application be not filed within two years of the first description of the invention in any printed publication, and within two years of the time when it was first in public use or on sale in the United States, no patent can lawfully be granted. Delicate questions sometimes arise as to whether an alleged use of the invention more than two years before was a "public use" within the meaning of the statute, or was merely an experimental use. It is not safe to take any chances in a matter of this sort, merely for the sake of having the term of the patent begin at a later date. When there are two applicants, each claiming a patent for the same invention, the patent is in some countries granted to the one who filed his application first. In the United States it is granted to him who first made the invention; and this, as explained above, means the one who first conceived ' and proceeded with diligence to reduce it to practice, either actually, or "constructively" by filing an application for patent. He who files the later application may therefore get the patent notwithstanding his tardiness; but in the absence of proof, it is presumed that he who filed first invented first; and he who files later has to sustain the burden of proof. This constitutes an additional reason for filing an application promptly. Knocking McGinnis owned a Billy goat, Mention The Technical World. 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WANTED-A student of the American School of Correspondence wants a position in a power plant. No experience. Address The Technical Months Free World, No. 302. If you are interested in any kind of investment, Oil, Mining, Plantation, Industrial, Lands, Stocks, Bonds, Mortgages, etc., send us your name and address and we will send you The Investor's Review for three months free of charge. A journal of advice for investors. Gives latest and most reliable information concerning new enterprises, Knowledge is power. Great opportunities come and go. Great fakes likewise. Get posted before investing Write to-day. INVESTOR'S REVIEW, 1580 Gaff Bldg., CHICAGO, ILL Have You Success? Every man contains within himself that Do you know that Jay Gould who died worth $100,000,000 began "HOW TO ATTAIN SUCCESS" is a text-book for those who will have success-it's not filled with nicely spun theories, but gives the master-key to your capacity and powers. 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