822 
sion’ engines and for the peculiar form of 
engine produced by omitting the inter- 
mediate cylinder from the latter, thus pro- 
ducing a machine with abnormally high 
ratio of cylinder-volumes, as successfully 
employed by Rockwood. A wide range of 
load was adopted and the result is found to 
be an efficiency, in the case of the novel 
form of engine, intermediate between that 
of the triple-expansion and that of the 
standard compound, approaching the effi- 
ciency of the latter as maximum expansions 
and minimum loads are approximated. We 
may be able to give later a fuller abstract of 
this paper. 
Mr. W.S. Keep details a series of experi- 
ments upon ‘ Cast Iron under Impact,’ in 
which he shows some very singular and 
puzzling phenomena, such as the increase 
of the strength of the metal by simply 
smoothing its surface, variation of the resist- 
ance and of the elastic limit by such alter- 
ations of its superfices, and similar hitherto 
unsuspected modifications of its molecular 
characteristics by this method of strain. 
Mr. George Richmond offers a study of 
“Thermodynamics without the Calculus,’ in 
which he develops in an interesting and 
peculiarly helpful manner the method of 
Professor Gibbs in the application of the 
temperature-entropy system of coordinate, 
thermodynamic geometry. The paper is 
presented in compliance with the request of 
members of the Society in the course of a 
discussion during the preceding meeting. 
Mr. Charles T. Main gives a very unique 
paper, on the ‘ Valuation of Textile Manu- 
facturing Property ;’ which important but 
greatly neglected department of technical 
literature has peculiar interest to the capi- 
talist and the economist as well as to the 
engineer. This study is in great detail, and 
its writer is an acknowledged expert. 
Mr. Fletcher submits an account, given 
by the inventor, who is still living at a ripe 
old age, of the invention and introduction 
SCIENCE. 
[N. S. Von. VI. No. 153. 
of the Stevens Valve-Gear for steam engines, 
universally employed for many years past 
on the ‘American river-boat engine.’ It is 
an interesting and valuable contribution to 
technical history. 
Other papers, numbering in all over 
twenty, are contributed by as many mem- 
bers, each expert in his own department, 
and affording material for another valuable 
volume of transactions. 
The next meeting will probably be at 
Niagara Falls. 
PRESIDENT GILMAN ON THE RELATIONS 
OF SCIENCE AND COMMERCE. 
At the annual banquet of the Chamber 
of Commerce in New York, November 23d, 
the chairman, Mr. Alexander EH. Orr, called 
upon President Gilman, of Johns Hopkins 
University, to respond to this sentiment, 
Commerce the Child of Science and its filial 
Supporter. The substance of Mr. Gilman’s 
remarks is indicated in the following re- 
port: 
Let me give some striking illustrations 
of the impulse that Commerce has received 
from Science; but let them all be drawn 
from present times, at least from days with 
which many men in this assembly are per- 
sonally familiar. 
Without astronomy there could be no 
sure navigation of the opensea. The great 
observatories, with their able masters and 
their powerful lenses, are revealing to 
human intelligence the celestial mechanism, 
and are making every year more accurate 
the nautical almanacs—those guides to the 
heavens, so sure and so important that we 
may almost call them ‘The Pilots’ Bible.’ 
It is to the science of naval architecture 
that commerce owes the marvelous improve- 
ments which have transformed the packets 
of the ‘ Black-ball’ line and the Baltimore 
clippers into the iron steamers of to-day. 
The size, materials, forms, structure, of sea- 
going ships, both men-of-war, protectors of _ 
