540 
MOUNTINGS TOR COAST ARTILLERY. 
of what are generally regarded as the Vavasseur type 1 2 supporting the 
gun trunnions. The slide is inclined at an angle of 9° to allow the 
gun to run up after firing, and the recoil is about 2 ft. 5 in. A steel 
shield 3 in. thick, sloping at an angle of 33°, is supported from the 
platform and the front of the slide. The general result is an extremely 
compact mounting. 
The training arrangements are duplicated, one set of training gear 
being placed on the right front of the mounting and worked under 
complete cover from the emplacement floor, the training arc (D) being 
close to the eye of the training number. A second training station 
(A) is provided on the loading platform. The elevating gear is also 
on the right front of the mounting and is worked under cover, an 
indicator dial (E) being attached to the recoiling buffer and driven by a 
chain from the trunnions. Chain gear is open to objections unless the 
tension is carefully adjusted, and I have since come to the conclusion 
that a sin gle bronze band pulling the dial round against a spring is a 
better arrangement. In order to check the elevation indicator at any 
moment, a stop can be provided on which the gun rests at extreme 
depression. 3 If this depression is once carefully ascertained by clino¬ 
meter and marked on the dial, the latter can be checked at any time 
by simply depressing the gun to the stop and adjusting the dial if it 
does not read correctly. Thus, unless the emplacement alters its level, 
a clinometer need never be used and the group commander can at any 
time satisfy himself in a few seconds that the indicator is reading 
correctly. Training and elevating gear works with perfect ease. 
Cases I., II. and III. are thus provided for; but the laying number 
can train only. Thus, when employing Case I., he must, by word or 
signal, direct the elevating number, while himself working the training 
gear. In Case II., he lays for line only and has full control of his 
gun. In either Case, I. or II., he can fire with his eye over his sights 
—a point which I regard as extremely important. 
For loading, a platform 4 ft. broad is provided, access being given 
by two comfortable curving staircases, one on each side. As shown in 
Plate I., the mounting was specially arranged so that its loading plat¬ 
form abuts against a fixed loading stage in the emplacement. This 
has the advantage that the mounting will traverse through a complete 
circle. In the case of two of these mountings, however, the loading 
i I am not able to ascertain the date of the earliest instance of this arrangement of a recoiling 
buffer carrying trunnions. The first R.C.D. official drawing showing this arrangement is dated 
12th March, 1880, where an exactly similar plan to that shown in Plate I. was applied to a proof 
truck for 10'4-in. and 12-in. guns. There are, however, sketches of earlier date. The first 
Vavasseur drawing which reached the department-^a design for the mounting of a 25-pr. R.B.L. 
gun—is dated 29th October, 1880. It is clear, therefore, that this arrangement was independently 
Invented in the R.C.D. The question of the invention of a buffer giving uniform resistance is 
more important. The “Naval Gunnery Manual, Part II., 1895,” roundly states: “Hydraulic 
brakes which offer a uniform resistance . . . exist in several different forms, but the principle 
of action is the same in all. They were originated by Mr. Vavasseur, and, in whatever form they 
exist, are essentially Vavasseur brakes.” This is quite inaccurate. The uniform resistance brake 
was first invented in the R.C.D. in the form in which it now exists, and the later rotating dise 
arrangement, introduced by Mr. Vavasseur, has been abandoned for the earlier R.C.D. form with a 
ralre key. To state these facts is in no sense to disparage the excellent and original work of Mr. 
Vavasseur. 
2 In the Mark I. 6-inch quick-firing mountings these stops are fitted. 
