March 23 '871] 
NATURE 
4It 

perverse defiarce of scientific principles. Why this 
should be is too large a question for present discus- 
sion, but the fact is bevond doubt. Take, for example, 
one of the most effective seats of national manufac- 
ture—the small-arm factory at Enfield, which is under 
the command of an officer who may fairly be cre- 
dited with scientific intelligence. You will see there a 
considerable amount of what may be called imported 
science. Outside inventions in machinery, in rifle barrels, 
in locks, in breech-actions, and other branches of the work, 

have been appreciated, adopted, and improved, and this is 
so far good. The Snider is a very clever makeshift, and 
perhaps as good a converted rifle as could have been made 
out of the old Enfield. The projected Henry- Martini, again, 
has an excellent breech-action, though not quite the best 
that might have been selected. Its barrel is ona good and 
tried pattern, although one that has not very successfully 
competed with the Metford. Inthese respects, the design 
cannot be called unscientific, but it is said that one essen- 
tial element of the new rifle—the sighting—if not abso- 
lately left to be fixed by tradition and routine, will be 
in principle little better than the worthless sighting 
of the old Enfield. If a crack shot were offered the 
choice between a first-rate barrel with clumsy and un- 
scientific sights and an inferior barrel fitted with perfect 
sights, he would certainly prefer to enter into a competi- 
tion with the latter weapon. Errors from defective aim 
are, as a rule, much larger than those due to imperfections 
of rifling, and to fit a first-rate weapon with bad sights is to 
throw away nearly all the skill and money which has been 
expended upon it. This is just what the people at Enfield 
are doing now, and all for want of familiarity with one 
of the simplest maxims of geometrical science. When 
a mathematician, an astronomer, an engineer, or even 
a superior artisan, wishes to determine with accuracy 
the position of a point, he almost invariably does it by 
setting off its distance from each of a pair of rectangular 
co-ordinate axes. In very special cases and for very 
special reasons the advanced geometrician will occasionally 
employ oblique instead of rectangular axes ; but whenever 
it is practicable, whether he is dealing with linear or 
angular measure, he uses as a matter of course rectan- 
gular axes. Ina case where he has to measure indepen- 
dent variations in horizontal and vertical directions, he 
would think it simply absurd to refer the position of a 
point to any other than a pair of horizontal and vertical 
axes of co-ordinates. Thus the astronomer has his co- 
ordinates of azimuth and altitude, of latitude and longi- 
tude, the builder works with his plummet and square, 
and the most simple-minded carpenter, who wished 
a nail put in a particular spot on a wall, would order 
it to be driven in at so many feet from the floor, and 
so many feet from the side of the room. This elementary 
scientific method has in fact descended to so lowa stratum 


of intelligent society that most people have assimilated it 
as if by instinct, and would open their eyes rather widely 
if they were told that when they practised it they were 
obeying the dictates of science. And yet, strange as it may 
seem, this extremely elementary, almost axiomatic, idea of 
rectangular co-ordinates, has not yet penetrated to the 
Government factory at Enfield. Consider what the sights 
of a rifle are for. In the simplest case, when you are aim- 
ing at an object the distance of which is known, and when 
there is no wind, you have nothing to do but to adjust the 

sights to the right elevation, and align them upon the 
object. But if your first shot falls low or high, or if you 
want to hit another object at a different distance, you 
must do one of two things, either slide your backsight up or 
down or elsetakea fuller or finer sight. In other words, you 
must correct the error in elevation, either by mechanical 
adjustment or eye-adjustment in the vertical direction. 
Practically, large and occasional changes are made by 
mechanical adjustment ; small and frequent changes by 
eye-adjustment. So again, if there is wind to allow for, 
you must either give the sights an apparatus for lateral 
adjustment (which, of course, would be quite inadmissible 
in a military arm), or, you must make the necessary 
allowances by eye-adjustment in the horizontal direction. 
The occasions which require vertical and horizontal cor- 
rections are quite independent of each other, the one 
class being functions mainly of distance, and the other of 
lateral wind. This is, therefore, precisely the case where 
the position of the sight should be referred to vertical and 
horizontal lines. 
Instead of doing this, our Government manufacturers 
give you a backsight, bounded by two oblique lines at a 
certain inclination to the vertical, and they provide you 
with a foresight, bounded by two other oblique lines at a 
different inclination to the vertical. When they indulge 
in a great effort of imagination they sometimes dream of 
getting rid of the oblique lines on the backsight, still 
leaving the foresight as bad as ever. Anything more per- 
versely unscientific can scarcely be imagined, though we 
daresay it will be stoutly defended on the plea that it is 
the same venerable system which contributed to the non- 
efficiency of Brown Bess, 
To any mechanician, however humble, it must be quite 
clear that both backsight and foresight ought to be 
bounded by horizontal and vertical lines. And here we 
might close the subject but for the stupendous power de- 
veloped by the military mind, of pooh-poohing suggestions 
which have only science and reason to recommend them. 
“ Extremely ingenious and scientific, no doubt,” our soldier 
critic may say, “* but shows a woeful ignorance of the prac- 
tical conditions of the problem. You see our recruits are 
not philosophers, but rough fellows, and we must give 
them something easy to understand and handle, and 
capable of bearing rough usage. Experience has shown 
that there is nothing like the old V backsight and 
knife-edge foresight, with which the British soldier can go 
