Springfield Furnace Co. v. Miller Down-Draft Furnace Co.

ADAMS, District Judge.

This is a suit for an alleged infringement of letters patent of the United States No. 447,179, dated February 24, 1891, granted to Melville C. Hawley, for a new and useful improvement in furnaces. There are three claims in the patent, the first of which only is in controversy here. That reads as follows:

“In a combined downward and upward draft furnace, the combination of the lower upward-burning grate, an upper downward-burning grate, an intermediate combustion chamber and escape flue leading from said combustion chamber, the bars in said upper grate being spaced widely…