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SELECT DISTINCT patent.*, YEAR(date) as year FROM patent WHERE (category = 'Relay') ORDER BY date ASC, patent, type

Total of 1 patents found where: Category is 'Relay';

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T / S Patent Date Description Patentee Category Assigned To
 1894
U 512,656 January 9, 1894 Relay
Method of making a telegraph relay more responsive		 LOCKE, Fred M.
 Relay  

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