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

Total of 2 patents found where: Category is 'Hole';

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T / S Patent Date Description Patentee Category Assigned To
 1913
U 1,055,322 March 11, 1913 Insulator
Holes (2) through insulator to pin allows lightning to pass to pin & ground
DE LONG, Harry A.
Hole  
 1916
U 1,206,846 December 5, 1916 Insulator
Hole in crown with mercury receiving ends of line wires & clamp
HOPKINS, Roy S.
Hole  

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