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PROFESSOR 0. REYNOLDS AND MR. W. H. MOORBT 
Appendix. 
Although no part of this research, it may be interesting to notice that reduced to 
the latitude of Greenwich this becomes 
777-07, 
and reduced to latitude 45° at sea level 
777-53. 
Exjiressed in metre-grammes and the centigrade unit of heat this last value 
becomes 
426-58. 
The value of g being 
980-63, 
we have for the mean value of the specific heat of water between 0° and 100° C., 
expressed in absolute C.G.S. units, 
41,832,000 ergs. 
Making use of IIegnault’s formula for the specific heat of water at difierent 
temperatures, this would give the mechanical equivalent of the heat required to raise 
1 lb. of water at 60°-5 Fahr. through 1° Fahr. at Manchester as 
773-74 ft.-lbs., 
and ta.king water at 32° Fahr., this gives 
773-07 ft.-lbs. 
Similarly expressing the result in absolute C.G.S. units, we have for the mechanical 
equivalent of the heat necessary to raise 1 gramme of water through 1° C. in latitude 
45° and at sea-level 
[a) From a temperature 15°-8 C. 41,660,000 ergs. 
(h) „ „ 0° C. 41,624,000 „ 
