The 20 guns ordered by Lincoln were manufactured by the firm of Goddard, Rice & Co. and sent to Washington D.C. in November 1861. The guns that they sent were four feet long, six inches in diameter at the breech and three and a half inches at the muzzle. It had a one and a half-inch rifled bore with fifteen lands and grooves. Opposing wedges, operated by handle went through the breech of the gun holding the breech - block in place. A truncated cone on the front of the breech-block forces against two tapered rings, to create the gas seal for the breech. (Much like the rings on a piston in an engine.) A handle on the back of the breech–block pulls the block back to break the rings free.