PROCEEDINGS 
OF THE 
GEOLOGICAL & POLYTECHNIC SOCIETY 
ffi tfce WLt&umnmQ of gorfcsijtte, 
AT THE FORTIETH MEETING, HELD IN THE GUILDHALL, 
DONCASTER, ON WEDNESDAY, AUG. 24TH, 1853. 
Edward Schofield, Esq., M.D., in the chair. 
The following gentlemen were proposed as Members of 
the Society : — 
Wif. Beckett, Esq., M. P., of Kirkstall Grange. 
Peter Fairbairn, Esq., of Woodsley House. 
John McLandsborough, Esq., C E., of Otley. 
Rev. Phipps Champneys, of Skellon, Doncaster. 
The Chairman, after briefly addressing the Society, and 
announcing the subjects of the communications to be brought 
before the Meeting, called upon W. S. Ward, Esq., of 
Leeds, to read the first paper — 
ON A NEW THERMOSTAT FOR REGULATING VENTILATION. 
BY W. S. WARD, ESQ., LEEDS. 
Mr. Ward said — Having been engaged in horticultural 
pursuits, he had found that it was desirable to have some 
instrument for regulating the ventilation and temperature of 
hothouses, without requiring the close attention of the gar- 
dener. He then described the invention which he calls a 
Thermostat, and which consists of metallic vessels, in which 
the vapour of a volatile liquid is used to give motive power for 
opening or shutting ventilators, or dampers, or regulating the 
VOL. III. 
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