582 TEANSACTIONS OF THE 



tion of an article, making it easy to identify the compositors wbo own 

 them. As the slips are corrected each compositor removes his slug, leaving 

 the matter in order for the " maker up." Dr. Y. claims to have invented 

 this ten years ago. 



Mr. Bruce read a long circular from Mr. 0. P. Stevens, of Cleveland, 

 Ohio, describing his grain-hulling and feed mill, and the advantages to be 

 derived from its use. These seem to be many and important, as it removes 

 only the least nutritious part of the wheat, and only a small percentage of 



Mr. Rowell read a communication from Mr. Pros&er, in relation to his 

 boiler, and to correct some statements made, in relation to it, by Mr. 

 Fisher, on a former occasion : 



New York, March 20, 1860. 



Mr. Fisher, in a "paper read before the Polytechnic Club of the Ameri- 

 can Institute, February 23d," doubtless intended to do my boiler full 

 justice ; but, I regret to say, that he has failed to do so, and hence, I feel 

 constrained to do it myself, lest my silence should be construed into indif- 

 ference of the principles of that invention, which has cost me so many 

 years of toil, and thousands of dollars ; or, still worse, that others should 

 be allowed to rob me of the merits of its invention. 



The first boiler, of the kind referred to, was built in 1855, (after making 

 expensive experiments at my own proper cost, charge and expense.) under 

 my own directions, and from my own drawings, on principles which bad, 

 for years previous, engaged my attention and my means. 



I was called upon to explain and defend it before the New York Steam 

 Fire Engine umpires, in 1856, and no one there, but myself, dared to 

 claim the invention ; and for the truth of my assertion, I appeal to those 

 gentlemen, viz : Messrs. William B. Leonard, Alderman Blunt, Gr. M. 

 Woodward and F. S Low. Thus much, in vindication of myself from a 

 rumor which Mr. Isherwood has sufi'ered to soil his excellent " Engineering 

 Precedents," vol. 2. 



The second paragraph, of Mr. Fisher's communication, is very erroneous ; 

 and as to the comparisons with the boilers of the " San Jacinto," I 

 entirely repudiate them as made, for reasons too obvious to need insisting 

 upon. My boiler had been in operation nearly two years when the trials, 

 referred to, were made — now nearly one year ago — and it is still in the 

 same condition as it was then, although it has never been blown oif, for 

 there is nothing but clean distilled water to blow off at any time. 



The evaporation, as recorded by Mr. Isherwood, exceeds 13 lbs. (more 

 correctly, 13.048, 13.106 E, 13.072 lbs.) of water at 212^* F., converted 

 into superheated steam by one pound of combustibles for each and every one 

 of the days to which the record refers. 



This, I believe, greatly exceeds anything ever before recorded, (under 

 the same circumstances,) having as good authority to support it, for there 

 was no priming, and no vesicular water. Another point which challenges 

 attention is the fact, that on the only day when the break was sufficiently 



