404 REPORT— 18G6. 



The experiments which the Ordnance Select Committee instituted for the 

 piirpose of obtaining a sohition to the foregoing questions must be regarded 

 as preUminary to any inquirj- into the larger question of the penetration of 

 iron defences by steel projectiles. No attempt has been made to found any 

 (tbsohife law of resistance upon the following results ; for these results are 

 not sufficiently extensive to warrant any such proceeding. They were car- 

 ried out for the purpose of affording a practical solution to the questions at 

 issue, and were limited in extent by considerations of expense. To found 

 any general law of penetration into iron defences would require a much more 

 extensive and costly trial; and although the results of such an investigation 

 might be highly interesting as a philosophical question, it is doubtful whether 

 they would prove of sufficient practical utility to warrant the unavoidable 

 expense*. 



AVhen it is considered that this question is surrounded by difficulties and 

 causes of error over which we have no control, it will appear that it is at 

 present hopeless to look for anything but an approximate result. The very 

 quahty of the materials we are obliged to make \ise of, the rougli and prac- 

 tical nature of the trials, and the necessity of carrj-ing them out on a 

 moderate scale, aU tend to make the cxj "riments, philosophically considered, 

 imperfect and insufficient as a basis for mathematical analysis. 



The following programme of experiments was determined on for the first 

 point : — 



Chm. — 6-3-inch M L i-ifled gun (Shimtf). 



Frojectiles. — Four descriptions of steel sliot, of the following weights, as 

 nearly as manufacturing limits will allow: — spherical 3o-o lbs., elongated 

 71 lbs., elongated 106-5 lbs., elongated 64 lbs. J, — all to be hemispherical- 

 headed, and of 6-22 inches diameter. 



Charges.— To be so arranged that each projectile may strike -with the 

 same " work "' stored up in it. 



Iron Plates. — Best roUed iron, 5^ inches thick, placed vertically at a dis- 

 tance of 100 yards, and unbacked. 



The programme for the second point was as follows : — 



Guns. — 6-3-inch M L rifled gun of 140 cwt. ; 7-inch M L rifled gun of 

 134 cwt. ; 100-poundcr smooth-bore gun of 61 tons (9-ineh). 



Projectiles^. — For 6-3-inch gun, same as detailed in the first programme ; 

 for 7-inch gun, elongated steel shot of 100 1)}S. weight and 6-92 inches dia- 

 meter ; for 100-pounder g-un, spherical steel shot of 104 lbs. and 8-87 inches 

 diameter. 



Charges. — To be so arranged that each projectile may strike with a "work" 

 proportional to its diameter, taking the 6-3-inch as the standard. 



Iron jilates. — Best rolled iron 5h inches thick, placed at a distance of 100 

 yards, and unbacked. 



* The experiments liitlierto carried out have given us a fair practical knowledge of tlie 

 conditions to be fulfilled in order that complete penetration tlirough iron defences may 

 be effected. 



Wo can predict, with a very close a]iproximation to the trutli, whether a given projec- 

 tile sti-iking with a given velocity, will or will not pei-forate a given ii-ou structure; but 

 supposing it not to be able to perforate it, we cannot say how far it wUl indent it, and it is 

 submitted that this is of little consequence. 



t The gun used in the first series of experiments against .'j-.^-incli plates was the experi- 

 mental G-3-inch gun of 140 cwt., lengtli of boro 126 inches. This enabled the necessary 

 high velocity to be obtained. 



\ Same weight as service-shot. 



§ Elongated projectiles were all lieinispheric;d-]ieaded. 



