HITTING! THE MARK, ETC. 
3 
In a languid melancholy way we have been arriving (for a 
reward of 200 years’ study of this question) at an inkling of 
the real state of the case. In gunnery our parabolic theory 
was all wrong. It was fancied, somehow, first of all that the 
resistance of the air had little power as against shot. Sir 
Isaac Newton and Dr. Halley were both of this opinion. 
Eobins states (“ Grunnery,” Preface), that a musket-ball at an 
elevation of 45° should range seventeen miles in vacuo, yet it 
only flies half a mile ! * 
The great honour of mastering the complicated difficulties: 
attending the determination of successive velocities at different 
points of the flight, and calculating the laws of the resistance 
of the air from experiments made upon a large scale, is unques- 
tionably due to our fellow-countryman, Professor Bashforth. 
This gentleman, apparently from the tenour of the Eeport, re- 
ceived little approval or encouragement from the official mind. 
The English public will no doubt appreciate these labours, 
and it is a matter of congratulation that such men as Profes- 
sors Adams and Stokes have undertaken the onerous task of pro- 
nouncing their verdict upon researches as profound as they were 
spontaneous. An elaborate Eeport is now published replete 
with results of the highest importance to the future defensive 
power of this country.f Quoting from this report we read : — 
dulums, under the name of Leur’s, and another by Boulenge, which give 
only one velocity, have been much used in this country and on the Con- 
tinent. Sir Charles Wheatstone, F.R.S., and Breguet, also designed instru- 
ments for measuring successive velocities, but no information is extant upon 
their experimental success. At Paris, in 1867, Schultz’s instrument was also 
exhibited with a similar intention and no result. 
* The resistance of the air in the case just mentioned reduces the range 
to a space thirty-four times less than a vacuum range. 
Hutton’s law assigned it to be a function of the velocity added to its 
square ( av + bv 2 ). 
Didion at a function of the velocity added to the cube (bv + cv 3 ). 
Colonel Mayewski at a higher function still — 
bv 2 + dv\ 
What is very remarkable is that Hutton and Piobert (whose laws have 
been commonly employed) deduced very different laws from the same ex- 
periments. 
For further information on this point see “Description of a Chronograph r 
adapted for Measuring the varying Velocity of a Body in Motion through 
the Air, and other Purposes.” London : Bell & Daldy. 
t Report on Experiments made with the Bashforth Chronograph for deter- 
mining the Resistance of the Air to the Motion of Projectiles (p. 169), 
Printed by Eyre & Spottiswoode, November 1870, for Her Majesty’s Sta- 
tionery Office. 
