98 Mr. Goldingham’s experiments 
A metre, according to the accurate investigations lately 
made in England, contains 39,37079 English inches, and 
therefore 341,54 metres will be equal to 1120, and 333,7 to 
1094,8 English feet. 
“ Some curious experiments were made relative to sound by 
Messrs, de Thury, Maraldi, and de la Caille, upon a line 
14636 fathoms in length, having the tower of Mount Lheri 
at one end, and the pyramid of Montmartre at the other 
extremity, their Observatory was placed between the two 
objects. The result of their observations was, that sound 
moves 173 French* fathoms in a second when the air is calm. 
2. That sound moves with the same degree of swiftness 
whether it is strong or weak, an explosion of half a pound 
of powder discharged in a box, having been heard in the 
same space of time, as the report of a great gun charged 
with nearly six pounds of powder. 3. That the motion of 
sound is uniform, its velocity neither accelerating nor di- 
minishing through the whole course of its progress. 4. That 
sound travelled at the same rate, whether the gun be pointed 
perpendicular to the horizon, or towards the person who hears 
the report, or from him — by other experiments however, 
the progress of sound appeared to be impeded by a strong 
wind.” Dr. G. Gregory, Econ. of Nat. 
The velocity in the foregoing table, stated to be Sir Isaac 
Newton’s, does not agree with that given by himself, which 
is 979 feet ; this however is not deduced from experiment, 
but from the theory, no regard being had to the thickness 
of the solid particles of air, through which sound is propa- 
gated. This being allowed for, according to the formula, 
* Or iio6| English feet. 
