25th June 1929, Page 68
	
	25th June 1929
			Page 68
		
					Page 68, 25th June 1929
									
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GEAR CHANGING A Résumé of Recently Published Patent Specifications. I N their specification, No. 311,252, the Hurefrey-Sandherg Co., Ltd., and T. B. Barrington describe a device......
					










































































































