INDEX. 483 
Pronouns, conjectures concerning the origin of, 93. 
R 
Reaction of effuent water, original experiments on, 235, et seg, 
_ Rew Dr. his remark on the controversy concerning the 
measure of moving force, 105'——his definition of equal 
moving forces, 179. 
Resolution of compound moving forces explained, 254, et seq. 
Respiration on, 15—bow it affects atmospheric air, 25 
quantity of air inspired each time equal to 30 cubie 
inches—number of inspirations in a minute, 20, &c. 
26—makes the same changes in air as the combustion of 
charcoal, 34. 
Rotten-stone, cursory remarks on, 313—is found on Bake- 
well-moor, Derbyshire, 314—supposed to be derived 
from black marble, 317 analysis of, 319. 
Ss 
Suarrs, Mr. John, his experiments on the force of steam 
compared with its heat, 1, e¢ seq. 
Smeaton Mr, on mistaken notions about the measure of 
force, 107—his definition of power in mechanics—is 
proportional to the square of the velocity generated, 129 
—or to the pressure multiplied by the space through 
which it acts, 142, 224—-his remarkable result with 
water-wheels in which the maximum effect. far exceeded 
that by the common theory, 160—important conclusion 
thereupon, 2bid—demonstrates that half the force of a 
body in motion is expended in certain circumstances in 
producing a change of figure, 181. 
Summer birds of passage, remarks on, 453—etables of the 
times of their migration. 
Space, in mechanics, one of the two elements of moving 
force, 223. 
Stanuore, Earl, his theory of the returning stroke applied, 
266. 
Steam, latent heat of, nearly the same at all temperatures 
in a given weight, 7, 8 and. 9—is equal to 920°, g; 
