Introduced the principle of lubricating the bullet for breach loading guns which was the salvation of breach loading guns. The guns were of no use before this. This was done in the winter of 1850.[220] [220] See Appendix B. NOTE 4 Before 1855 all annealing and case hardening was done with Char coal which was very expensive. About this time in Hartford I introduced the plan and furnaces for using hard coal which proved a great success and is now used everywhere for both case hardening and annealing. Many other improvements on gun work and machinery which I have made might be mentioned, but the above is sufficient. APPENDIX B THE JENNINGS GUN “Reminiscences of the first magazine rifle. Most important discovery by R. S. Lawrence of this city (Hartford, Conn.).--Original use of lubricating material in fire arms.” A few days ago Mr. A. E. Brooks of this city (Hartford, Conn.) received a very curious and interesting magazine gun from New York, bearing the name of Ex-Superintendent R. S. Lawrence of the street department as the manufacturer. Conceiving that there must be a good story connected with the arm which was one of the first magazine guns ever made in this country, a reporter of _The Post_ sought out Mr. Lawrence and learned the history of the gun. “The rifle which Mr. Brooks brought to my notice, with my name on it,” said Ex-Superintendent Lawrence, “is one of a lot of 5,000 manufactured at Windsor, Vermont, by Robbins & Lawrence, for Mr. Courtland C. Palmer of New York. This rifle was known as the Jennings gun. A portion of the lot was then called single loaders, and a portion repeating rifles, carrying twenty charges. The charge of powder was contained in the ball, consisting of twenty-two grains of powder only. With the repeating rifle I have often fired twenty shots within one minute, but not with any accuracy, for the reason that all breech-loading guns up to this time used what is called the naked ball without any patch or lubricating material. The result in firing the gun was that the ball leaded the barrel, by building on, to such an extent that in firing twenty shots from a 50-100 calibre bore there would be a hole in the barrel less than 25-100.”