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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 = '32') ORDER BY date ASC, patent, type

Total of 7 patents found where: Class is '174'; Subclass is '32';

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T / S Patent Date Description Patentee Category Assigned To
 1868
U 75,492 March 10, 1868 Improvement in Telegraph Poles
Wire wrapped pole and crossarms to carry leaking electricity to ground		 VARLEY, Cromwell F.
 Wire  
 1880
U 224,580 February 17, 1880 Induced Current Guard for Electrical Conductors
Pre-transposition technique to eliminate induced current on telephone and telegraph wires		 CHINNOCK, Charles E.
 Transposition  
 1883
U 287,092 October 23, 1883 Mechanism for Preventing Induced Currents in Telephone Lines
Pre-transposition technique to eliminate induced current on telephone and telegraph wires		 BRENNAN, James W.
ROUSSEAU, Necter
 Transposition  
U Specimen known 289,890 December 11, 1883 Telegraph and Telephone Conductor
Lightning rod insulator system to protect telephone lines from cross talk		 CHAMBERS, Josephus C.
 Lightning Rod Insulator Vine, Jackson, Gridley
U 289,891 December 11, 1883 Telegraph and Telephone Cable
Lightning rod insulator system to protect telephone lines from cross talk		 CHAMBERS, Josephus C.
 Lightning Rod Insulator Vine, Jackson, Gridley
 1884
U 297,683 April 29, 1884 Telephone Line
Insulator and pin coated with waterproof compound		 DOOLITTLE, Thomas B.
 Miscellaneous  
 1886
U 343,014 June 1, 1886 Means for Preventing Disturbances on Telephone Lines
Pre-transposition technique to eliminate induced current on telephone and telegraph wires		 DANN, John E.
LAPP, John
 Transposition  

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