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SELECT DISTINCT patent.*, YEAR(date) as year FROM patent LEFT JOIN name ON name.patent = patent.patent AND name.type = patent.type LEFT JOIN category ON category.patent = patent.patent AND category.type = patent.type WHERE (category.class = '191') AND (category.subclass = '29R') ORDER BY last_name DESC, first_name, date, patent, type

Total of 2 patents found where: Class is '191'; Subclass is '29R';

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T / S Patent Date Description Patentee Category Assigned To
 WILGUS, William J.
SPRAGUE, Frank J.
U 908,180 December 29, 1908 Third Rail
Third rail insulator system (Ohio Brass)
WILGUS, William J.
SPRAGUE, Frank J.
Third Rail  
 STEWART, JR., Samuel B.
U 771,334 October 4, 1904 Third Rail Insulator
U-shaped third rail insulator metal caps fitting over each part to support rails.
STEWART, JR., Samuel B.
Third Rail General Electric Co.

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