THE ROYAL ARTILLERY INSTITUTION. 
161 
THE RANGE-FINDER. 
BY 
CAPTAIN NOLAN, E.A. 
The range-finder has now been in use for some years, and although several 
descriptions of it have been already given, I believe the present to be an appro¬ 
priate time for publishing a fresh account of an instrument which will 
probably be soon tried upon a large scale. 
To show the necessity for the employment of the range-finder with 
artillery in the field, it is essential to prove three points :— 
1st—That the range-finder can give the correct distance of an object in 
a time and fashion applicable to a battery in the field. 
2ndly—That to know the distance of an enemy is of the utmost import¬ 
ance to artillery. 
3rdly—That it is improbable that this object can be effected by any 
other instrument differing essentially in construction from the range-finder. 
I.* —That the Range-Finder can give the correct Distance oe an 
Object in a time and in a eashion applicable to a Battery 
in the Field. 
The proofs adduced upon this point are entirely experimental. 
In Vol. VII., Part 2, p. 136 of the “ Proceedings of the Department 
of the Director-General of Ordnance,” will be found an account of an 
experiment which took place at Shoeburyness on the 21st June, 1869, before 
Colonel Elwyn, Superintendent of Experiments. 
Four telemeters, designed respectively by Mr. Adie, celebrated as an 
optician and inventor; by Colonel Clerk, R.A., Superintendent Royal Carriage 
Factory ; by Messrs. Elliott, the great instrument makers, of the Strand, 
London; and by Lieut. Nolan, R.A., were employed on this occasion. 
[yol. VIII,] 21 
