484 
MINUTES OF PROCEEDINGS OF 
experiments being a 120-pr. shunt rifled gun, throwing a 140 lb. shot, with 
an 18 lbs. charge. 
The result was not considered favourable, owing to the shearing of the 
tongues, and the fracture and displacement of the bars. The Committee in 
their Eeport state that, 
“ The fixing together of the bars presents a difficulty of construction which 
it may not be easy to overcome. It is to be observed, that the first experiments 
were made with targets only 4 or 5 ft. high, whilst, if applied to casemated forts, 
they could not well be less than 8 ft. high; and that, therefore, the difficulty of 
keeping together a large number of bars was not experienced in any great degree.” 
The great recommendations of this plan,—viz. simple rolled bars of iron 
with tongues and grooves,—are simplicity and economy, the cost being only 
about £16 a ton; and the Special Committee on Iron appear to consider it 
still worthy of consideration, for in their final report, in alluding to shields 
of this nature, they state that although their experiments have not warranted 
them in recommending it for adoption, “ further experiments are needed to 
justify a decided conclusion respecting this plan.” 
The most successful plan which has 
yet been tried for protecting embrasures 
in casemated or open coast batteries is 
Captain Xnglis's shield, of which the 
accompanying sketch represents a sec¬ 
tion. 
It consists of planks of wrought- 
iron, (Cy D,) crossing each other in 
alternate layers, and secured by screw- 
bolts passing through their centres. 
The shields are supported by diagonal 
boiler-plate struts (A) at each end, 
secured to a strong iron beam in rear 
built into masonry, these shields are 
otherwise independent of the masonry * 
The record of experiments on a shield 
of this description, which has been tested 
at Shoeburyness will be found in the 
“ Proceedings in the experiment on 
No. 1 shield (15" thick, in three planks, 
on one half its area, and 10" thick, in 
two planks, on the other half,) a total weight of 1972 lbs. of cast-iron 
shot struck the target at 200 yds. range from guns of various calibres 
from a 40-pr. Armstrong rifled gun up to a 12-ton 10*5" smooth-bore gun. 
The Committee reported that they considered the result of the experiment 
very satisfactory, “ as at its conclusion, the shield was capable of affording 
very good protection; the struts stood remarkably well.” and they 
pointed out that this method of construction “ combines strength, simplicity 
and cheapness of manufacture.” 
* This is a great advantage, as however much of the masonry in the vicinity of the shield may 
be displaced, the gun and detachment would still be protected, 
f Vide Vol. Ill, pp. 224, 253. 
