THE CORROSION OF IRON AND OTHER METALS 659 



carbon dioxide entirely from glass surfaces, although this has 

 long been recognised ; a very large area of glass was exposed 

 within their apparatus, especially in the vessel in which the 

 oxygen was stored. A simple apparatus such as Friend used 

 is in reality far better suited to such an inquiry than the 

 highly complicated apparatus used by Lambert and Thomson. 

 But simple conditions are usually adopted by all experimenters 

 only as a last resort. 



H. E. A. 



