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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 = '174') AND (category.subclass = '25R') ORDER BY date ASC, patent, type

Total of 1 patents found where: Class is '174'; Subclass is '25R';

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T / S Patent Date Description Patentee Category Assigned To
 1875
U 165,535 July 13, 1875 Improvement in Underground Telegraph Lines
Underground cable insulated by wrapping with cotton, hemp, or jute and saturating it with paraffin.		 BROOKS, David
 Cable  

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