310 SCIENCE IN SHORT CHAPTERS. 



London upon building stones, I have but to name the 

 Houses of Parliament, which have only been rescued from 

 superficial ruin by the patchwork replacing of certain 

 blocks of stone, and various devices of siliceous and other 

 washings that have been carried out at great cost to the 

 nation. That such an unsuitable material should have 

 been used is disgraceful to all concerned. The ruin com- 

 menced before the building was finished. At the time 

 when its erection commenced there were abundant evi- 

 dences of the ruinous action of London atmosphere on 

 some kinds of stone and the capability of others to resist 

 it, for while many modern buildings are peeling and crum- 

 bling, some of the oldest in the midst of the city show 

 scarcely any signs of corrosion. 



The Birmingham and Midland Institute was established 

 and in practical operation a few years before the present 

 noble building was erected. I was the first teacher there 

 and conducted the Science classes in the temporary premises 

 in Cannon street. Having observed with some interest 

 the disintegration of St. Philip's Church and other build- 

 ings, I was anxious for the safety of the new Institute 

 buildings, and accordingly made some experiments upon 

 the material proposed to be used by the architect. My 

 method of testing was very simple, and as the practical 

 result has verified my anticipations I think it might be 

 adopted by others. 



First, I immersed some lumps of the stone in moderately 

 strong solutions of sulphuric and hydrochloric acids suc- 

 cessively, and observed whether any visible action occurred 

 after some days. There was none. I then roughly tested 

 the crushing pressure of small samples in their natural 

 state, and subjected similar sized pieces to the same test 

 after they had been immersed in the acids. I found thus 

 that there were no evidences of internal disintegration even 

 after several days' immersion, and therefore inferred that 

 the stone would stand the acid vapors of the Birmingham 

 atmosphere. This has been the case with that portion of 

 the building that was built of the material I tested. As I 

 know nothing of the stone which is used for the extension 

 of the building under the present architect, Mr. Chamber- 



