Miscellaneous — The Preservation of Meteoric Irons. 47 



after taking his degree lie joined the United States Geological 

 Survey, carrying out work in Dakota and Colorado in conjunction 

 with Whitman Cross and S. E. Emmons. His most important 

 Survey work was a memoir on the Leadville district of Colorado. 

 In 1903 he was appointed professor of geology at the University of 

 Wisconsin and afterwards at Lehigh University. In 1907 he 

 "became professor of economic geology at the Sheffield Scientific 

 School at Yale. He was also editor of Economic Geology from its 

 commencement in 1905 until his death. When the United States 

 declared war he entered the Army, and soon left for France with the 

 rank of captain. At first engaged in railroad work, he subsequently 

 became instructor in a school of mining and engineering as applied 

 to warfare. Hard work and unremitting attention to duty wore 

 him out, and he succumbed to pneumonia following influenza, to the 

 deep and lasting regret of all who knew him, both in the Army and 

 in the scientific world. 



MISCELLANEOUS. 



On the Discovery of a Method op arresting the Decomposition of 

 Meteoric Irons, applied successfully to Meteorites in the 

 British Museum (Natural History). 



Henry Gadsdon (1861-1918), who died on December 2, aged 

 57 years, had been for over ten years employed at the Natural 

 History Museum as french-polisher. He was an excellent workman 

 of the best type, one who took pride in maintaining the high 

 quality of his work. It is thanks to his aid that the problem of 

 safeguarding the Meteoric Irons in the National Collections has — so 

 it is hoped — been successfully solved. Every curator who has had 

 such specimens under his care knows well the difficulty of preventing 

 them from rusting. The chief agent in causing the mischief appears 

 to be the unstable protochloride of iron— lawrencite — which 

 immediately breaks down in the presence of damp. This substance 

 is disseminated through certain specimens in extremely thin veins, 

 and, since the change that takes place causes it to swell, such 

 specimens are often found to be split across ; further, as a result of 

 the alteration of the lawrencite the nickel-iron alloy which is the 

 principal constituent of the meteorite is attacked, and finally 

 nothing is left of the specimen but a lump of rusty fragments and 

 powder. By keeping the air in the case as dry as possible, the 

 rate of attack may be slackened, but only slackened ; the ultimate 

 end is just as sure and inevitable. Varnishing the specimen is more 

 effective, but this process completely spoils the specimen for 

 exhibition purposes. Six years ago, in 1912, as the result of 

 experiments made on pieces of steel exposed to the weather, it was 

 thought that coating the meteorites with a thin, transparent film of 

 shellac by the process of french-polishing might overcome the 

 difficulty without sensibly interfering with the appearance of the 

 specimens, and the Keeper of Minerals decided to have first those 

 specimens which showed considerable signs of rusting treated in this 



