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for securing heavy armour plates to ship's sides. The Committee in their 
Report on the experiment state :— 
“ The defects of the fastenings were very apparent, as shown by the large number 
of bolts broken* (after the firing of only four rounds), thus causing the plates to 
buckle to such an extent, that in the case of a ship at sea they would soon roll off. 
The prevention of buckling is of very great importance, and the Committee are 
confirmed in the opinion they have expressed in their Report, viz. that * the bolts 
used as fastenings should be at least two inches in diameter.’ ” 
It is greatly to be feared that in the event of the early specimens of our 
iron-clad fleet being put to the practical test of war, the small bolts and the 
absence of elastic washers will be found very serious defects. It always 
struck me that the Portsmouth experiments led to a good deal of miscon¬ 
ception on this part of the subject. Any one referring to the records of the 
Iron-plate'experiments which have been carried on at Portsmouth and at 
Shoeburyness, will find that the endurance of the armour plate bolts is 
almost invariably favourably noted in the Portsmouth experiments, and 
almost invariably ^favourably in all the earlier Shoeburyness experiments, 
although the diameter of bolt used was the same in both cases. I think 
this apparent discrepancy is easily reconciled when it is remembered that 
the iron plates at Portsmouth are always attached to wooden ships, whilst 
the experiments at Shoeburyness have been chiefly on targets with iron 
skins, the strain on the bolt being thus much greater in one case than 
in the other. It must, however, be remembered that the practical test, if 
one ever takes place, will be in many cases under the conditions tested at 
Shoeburyness, and it is therefore to be regretted that bolts of larger diameter 
and elastic washers were not earlier adopted; for experiments have proved 
that by using bolts of larger diameter (2J or 3 inches) and elastic washers 
under the nuts a tolerably secure fastening can be obtained, and one which 
will prevent the buckling and distortion of the plates. 
The next construction for consideration is that adopted in the “Belle- 
rophon." But before passing on to a description of this class of ships it 
is desirable to notice some other experiments which were made at Shoebury¬ 
ness between 7th July 1862, and 8th December 1863, the dates of trial of 
the “ Minotaur " target, and of the “ Bellerophon 99 target respectively. 
We have seen that the “ Warrior" and the “Minotaur" are iron ships 
protected by iron armour plates on wooden backing, but at the date of the 
appointment of the Special Committee on Iron, no point was more in dispute 
than the combination of iron and wood in armour-clad vessels, as it was con¬ 
sidered by many that the timber backing would soon rot,t and afforded at best 
but a bad support to the plates, and it was, therefore, argued that iron ships 
protected solely by iron plates, was the proper plan for armour-plated vessels. 
The relative value, for resistance to projectiles, of wholly iron structures, 
and those with wooden backing, (such as the “Warrior"), could only be 
ascertained by experiment, for we And the names of Armstrong, Fairbairn, 
Samuda, Scott Russell, and others as advocates of the former, whilst those of 
Hardy (of the Thames Iron Works), Hewlett, Lancaster, and Mallet are on 
the side of the latter. This being the case several targets, composed wholly 
* In a report by Commander Colhoun, U.S. Navy, to Rear Admiral Lee, dated June 23, ’64, it is 
stated, “ On the 21st instant, the “ Saugus ” was struck only once by a round shot near the centre of 
the deck, a few feet from the turret; thence glancing, it struck the turret, breaking six (6) bolts.” 
f A plan has been tried of passing a gas flame over the surface of the timber previous to 
affixing the armour plates, with a view of preventing decay. 
