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To speed up the launching of lifeboats rushed to the rescue of sinking or distressed ships off the English coast, the British royal national lifeboat institution recently tested a tractor and auto trailer that hauled a lifeboat and crew to the aid of a ship off the dangerous shore of Dungeness, on the English Channel. The tractor, named the "F. W. D. Roadless," brought the lifeboat over a rough shingle road to the shore and then launched it by pushing the boat and its carriage into the sea. The tractor then backed, and by an ingenious device, pulling on a cable which travels around a pulley at the rear end of the boat and passes to the bow, pulled the lifeboat off the carriage and sent it in a seaward direction. When the launching had been accomplished, the auto tractor hauled the carriage to the shore, while the seven-ton lifeboat rowed out to the distressed ship. On loose shingle and sea-soaked sandy shores, the new auto tractor has operated successfully.

 

Positive prints of drawings and other subjects, that are said not to fade and that can be made as easily and as economically as blueprints, are prepared from a positive under a patented process. Dark lines are revealed on light tinted paper as in the original and are not reversed. No liquid or water is used; the undeveloped print, after exposure, is merely inclosed in a box containing a dish of ammonia water or any compound which gives off ammonia fumes. These act upon the paper to produce the picture. The print can be removed in five or ten minutes and needs no further attention.

¶ Popular Mechanics Magazine does not publish the name of the maker or seller of any device described in its pages, but this information will be furnished free upon application to our Bureau of Information. 