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SELECT DISTINCT patent.*, YEAR(date) as year FROM patent LEFT JOIN category ON category.patent = patent.patent AND category.type = patent.type WHERE (category.class = '335') AND (category.subclass = '236') ORDER BY date ASC, patent, type

Total of 1 patents found where: Class is '335'; Subclass is '236';

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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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