Manchester Memoirs, Vol. Iv. (191 1), No. ^4. 



XXIV. An Account of some Remarkable Steel Crystals, 

 along with some Notes on the Crystalline 

 Structure of Steel. 



By Ernest F. Lange, 

 M.I.Mech.E., Assoc.M.Inst.C.E., M.I. & S.Inst., F.C.S. 



Read May glh, igii. Received for publication June 20th, iqii. 



The natural occurrence of freely developed crystalline 

 forms in steel has been so rarely observed, that, with the 

 kind permission of Messrs. Vickers Ltd., I have pleasure 

 in bringing before your notice the most perfect example 

 of the free development of a large group of steel crystals 

 with which I am acquainted. These crystals were dis- 

 covered by Colonel T. E. Vickers, C.B., who happened to 

 be examining the pipe in a large rising head which had 

 just been removed from a heavy steel propeller-boss 

 casting, and who noticed their presence in the upper part 

 of the cavity. Impressed with the metallurgical import- 

 ance of the find, he had the mass of metal carefully sawn 

 in two, and the hollow portion freed from the surrounding 

 mass, and the cavity thus revealed photographed, as a 

 permanent record of its appearance. This photograph is 

 just half the natural size, and, as you will see from the 

 copy before you, it shows the cavity incrusted all over 

 with " pine-tree " shaped crystals in various stages of 

 development. The vertical crystals have formed with 

 remarkably little interference, some being separate, and 

 in a few cases reaching the remarkable length of 14 or 

 15 inches. (See Fig. i, Plate /.). 



August 2 1st, ign 



