372 
Loan Collection of Scientific Apparatus [July, 
I. Meteorological and Physical Apparatus made and used 
by Dr. Dalton. 
Throughout his life Dalton devoted much time and atten- 
tion to the study of meteorology ; indeed his first work, 
published in 1793, was entitled “ Meteorological Observa- 
tions and Essays,” and his last paper, printed in 1842 
(Mem. Lit. and Phil. Soc., vi., 617) consists of auroral ob- 
servations. Hence the first of Dalton’s apparatus which 
claim attention are the meteorological instruments. 
No. 1 is Dalton’s mountain barometer, with accompanying 
thermometer, made for him by the late Mr. Lawrence 
Buchan, of Manchester. The barometer is enclosed in a 
wooden case, which Dalton was accustomed to carry in his 
hand. 
Several home-made barometers used by Dalton in his 
observations are in possession of the Society. They are all 
of them filled, and the scales prepared, by Dalton himself, 
and are simple syphon tubes with a bulb blown on at the 
bottom to serve as a mercury reservoir. These are attached 
to plain pieces of deal, upon the upper part of which the 
paper scale is pasted. One of these, which has probably 
also served for tension experiments (No. 2, has been placed 
in the collection. 
Many of the thermometers appear also to have been 
home-made. 
No. 3 is a mercurial thermometer, evidently made and 
graduated by Dr. Dalton, and marked with his initials, J. D. 
The freezing-point of this thermometer was tested recently 
by Mr. Baxendell, who found that it had not altered since 
the instrument was graduated. 
Another (No. 4) is of the same kind, and bears date 1823. 
No. 5 is a third mercurial thermometer with long stem 
and wooden scale. 
No. 6 is an alcohol thermometer with wooden scale. 
No 7, a registering maximum and minimum thermometer 
employed by Dalton ; maker’s name, J. Renchetti, 29, Bal- 
loon Street, Manchester. 
II. Apparatus constructed and used by Dalton in his Researches. 
(1) “On the Constitution of Mixed Gases,” (2) “ On the 
Force of Steam or Vapour from Water or other Liquids at 
Different Temperatures, both in a Torricellian Vacuum and 
in Air,” (3) “ On Evaporation,” and (4) “ On the Expansion 
of Gases by Heat” (by John Dalton, “ Mem. Lit. and Phil. 
Soc. of Manchester,” 1st series, vol. v., part 2). 
