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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 = '219') AND (category.subclass = '388') ORDER BY date ASC, patent, type

Total of 1 patents found where: Class is '219'; Subclass is '388';

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T / S Patent Date Description Patentee Category Assigned To
 1923
U 1,451,815 April 17, 1923 Rapid Decorating Firing Furnace or Kiln
Kiln for firing porcelain spark plug insulators		 DAVENPORT, Ransom W.
 Manufacturing Jeffery-Dewitt Co.

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