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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 = '425') AND (category.subclass = '444') ORDER BY date ASC, patent, type

Total of 3 patents found where: Class is '425'; Subclass is '444';

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T / S Patent Date Description Patentee Category Assigned To
U 686,755 November 19, 1901 Machine for Making Insulating Tubes
Automatic wall tube making machine. Likely assigned to the Akron Smoking Pipe Co.
PALMER, Charles H.
FENTON, Curtis
U 759,429 May 10, 1904 Machine for Heading Insulators
Machine for forming the heads on pottery or porcelain wall tubes
Wall Tube  
U 1,469,584 October 2, 1923 Tube Forming Machine
Machine for making porcelain wall tubes
CASE, Francis M.
Wall Tube Federal Porcelain Co.

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