THE SMALLEST STEAM ENGINE ON EARTH

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408 N. 6th St., Wahpeton, North Dakota 58075

The enclosed article was copied from the January-June 1907 Scientific American. We found it interesting and thought others might also. There was also a picture, but wasn't clear enough to reproduce without special equipment. I wonder if anyone has ever in recent years seen or heard of this little engine. If so, I would like to know it's where-about, etc.

We really enjoy the Iron-Men Album and Gas Engine Magazine, including the kids, as my husband collects and restores engines it is of special interest to us.

What is perhaps the smallest stationary engine ever constructed has been recently completed at his shop on Yonge Street by Thomas H. Robinson, watchmaker of Toronto, Ontario. Smaller than a common housefly it slips easily into a '22 short' empty cartridge with plenty of room to spare. It weighs complete just 4 grains troy. This is 120 engines to the ounce, 1920 to the pound, and 3,840,000 to the ton. The horsepower is 1/498,000 part of a horsepower, and the speed is 6,000 revolutions per minute. The vibrating piston rod when running at this speed emits a sound like that produced by a mosquito. The bore of the cylinder is 3/100 of a inch. The stroke is 1/32 of a inch. The cylinder and piston rod, shaft and crank are of steel. The engine bed and stand are of gold. The balance wheel, which has a steel center and arms, with a gold rim, weighs 1 grain, and measures 3/16 of an inch in diameter. The shaft runs in hardened steel bearings fitted to the gold bed. Seventeen pieces were used in making the engine which is mounted on an ebony stand, inside of which are the brass connections, which convey the compressed air used to operate the engine to the hollow base of the engine. It was exhibited by request before the Canadian Institute in Toronto recently. When running, no motion is visible to the unaided eye, but by means of magnifying glasses and lantern slikes, which show the construction, an examination was made, and the opinion was freely expressed that the engine is the fastest of its size on earth. The calculations of both speed and horsepower were made by Prof. C. A. Chant of the Physical Dept. of Toronto University.