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A NEW COLLIMATING-TELESCOPE GUN-SIGHT FOR LARGE AND SMALL 
ORDNANCE. By SIR HOWARD GRUBB, F.R.S., Vice-President, Royal 
Dublin Society. 
(Pratrg XXYVI_) 
[Read, Marc 20th, 1901. ] 
WHEN it is necessary to point any instrument at an object, whether it be a rifle, or 
a gun, or a telescope, it is usual to do so by glancing at the object along the axis 
of the instrument, or some member or part which is parallel to the axis, bringing 
this part as nearly as possible into the line of sight between the eye and the 
object aimed at. This is done instinctively, without any education or instruc- 
tion, and it is curious to note that in this, the twentieth century, the most 
primitive and unscientific method still endures, and is used in all but exceptional 
cases for sighting purposes In our most modern weapons. 
It is true, of course, that for the more delicate operations involved in 
geodetical surveying, and in astronomical work where greater accuracy is a 
necessity, the telescope is used to determine the bearing or direction of objects, 
and of late years, the same has been applied to the directing of some of our 
larger ordnance; still the fact remains, that notwithstanding the ingenious and 
sometimes complicated refinements applied to guns of various types for the 
elimination of errors due to the trajectory, drift, windage, &c., the ultimate 
sighting, or laying of the gun in that particular direction which will cause the 
projectile to hit the target, is effected by this same primitive method, which, 
though capable of giving wonderfully good results in the hands of highly skilled 
and experienced marksmen, is hardly adequate for modern requirements. 
Even the most cursory student in such matters cannot fail to have noticed 
that, as a result of the labours of successive generations of military and mechanical 
engineers and scientific men, modern weapons of war have been developed to an 
extent beyond all expectations, and yet, notwithstanding all these improvements, 
the survival of all that is good from the vast labour that has been expended on 
the subject, the ultimate operation of laying the sights of a modern gun is the 
same in principle and in effect as that used with the weapons of medizeval 
aes. 
TRANS. ROY. DUB. SOC., N.S. VOL. VII., PART X. 2 NC 
