Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired
Application number
CA757842A
Inventor
C. Caldwell Frederick
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
E L CALDWELL AND SONS
Original Assignee
E L CALDWELL AND SONS
Publication date
Application grantedgrantedCritical
Publication of CA757842ApublicationCriticalpatent/CA757842A/en