8 a Count Rumford’s Enquiry concerning the Nature of Heat , 
manner: the two instruments used in the experiment, placed 
on their wooden stands, being set down on the floor, were filled 
to within about i-§- inch of the tops of their cylindrical necks 
with boiling hot water; and, a thermometer being put into each 
of them, they were placed, at the distance of 3 feet from each 
other, on a large table, in a corner of a large quiet room,* where 
they were suffered to cool, undisturbed. Near them, on the same 
table, and at the same height above the table, there was placed 
another thermometer, (suspended in the air, to the arm of a 
stand, )by which the temperature of the air of the room was 
ascertained from time to time. 
No person was permitted to pass through the room, while an 
experiment was going on ; and, in order to prevent, as far as 
it was possible, all those currents of air in the room which were 
occasioned by partial heat, produced by the light which came in 
at the windows, the window-shutters were kept constantly shut ; 
one of them only being opened for a moment, now and then, 
just to observe the thermometers, and note down the progress 
of the experiment. 
The results of each experiment were entered on a separate 
sheet of paper ; which paper was previously prepared for that 
use, by being divided into separate vertical columns, by lines 
drawn with a pen, and ruled in parallel horizontal lines with a 
lead pencil. 
The following is an exact copy of one of these register-sheets ; 
and contains the results of an actual and very interesting expe- 
riment, which lasted 2 6 hours. 
* This room, which is adjoining to my laboratory, in my house at Munich, is 19 
feet wide, 24 feet long, and 1 3 feet high. 
