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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 = '257') ORDER BY date ASC, patent, type

Total of 3 patents found where: Class is '257';

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T / S Patent Date Description Patentee Category Assigned To
 1878
U 208,487 October 1, 1878 Bottle Stopper
Bottle stopper
OAKMAN, Samuel
Bottle  
 1894
U 515,779 March 6, 1894 Strain Insulator
Strain type
LUSCOMB, Henry H.
Strain The Johns Pratt Co.
 1920
U 1,335,801 April 6, 1920 Insulator
Electrose strain (Brown p. 69)
STEINBERGER, Louis
Electrose  

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