CHEMICAL SCIENCE. 207 



THE DISINTEGKATION OF BUILDING STONES. 



Prof. Thomson, in a paper before the British Association, 1862, 

 showed, first, that the crumbling away of stones in buildings usually 

 occurs in the greatest degree at places to which, by the joint agency 

 of moisture and evaporation, nitrates and other salts are brought and 

 left to crystallize ; secondly, that the solidification of crystalline mat- 

 ter in porous stones, whether that be ice formed by freezing from 

 water or crystals of salts formed from their solutions, usually produces 

 a disintegration, not, as has been commonly supposed, by expansion 

 of the total volume of the liquid with the crystals during the growth 

 of the crystals, producing a fluid pressure in the pores ; but, on the 

 contrary, by a tendency of growing crystals to increase in size even 

 where to do so they must push out of their way the porous walls of 

 the cavities in which they are contained, and even though it be from 

 these walls that they receive the materials for their increase. 



CHEMICAL MEMORANDA. 



Improvements in Matches. In the place of sulphur for coating 

 matches, thereby rendering the wood more inflammable, an Eng- 

 lish company have introduced parafiine ; and matches thus prepared 

 are not likely by the vapors they generate to tarnish silver surfaces 

 and dyed fabrics. Paraffine matches are found to withstand damp- 

 ness in a most remarkable manner. 



Amorphous Phosphorus and its Practical Applications. The dis- 

 covery that phosphorus is capable of existing in a condition in which 

 it is no longer spontaneously inflammable has been turned to account 

 in the manufacture of matches, which cannot be ignited by friction 

 anywhere except on the prepared surface of the box which contains 

 them. The secret of the contrivance is, that the chlorate of potash 

 compound, tipping the match, is destitute of phosphorus, which in 

 the amorphous form is placed on the sand-paper ; hence these matches 

 are perfectly safe from accidental ignition, and moreover are not 

 poisonous. 



Comparative Fusibility of Iron. MM. Minary and Kesal state that 

 the fusibility of iron augments with the proportion of oxygen which 

 it contains : thus, in placing side by side, in a blast furnace, two cru- 

 cibles containing iron shavings of the best quality, but adding to the 

 second a certain proportion of oxide of iron, after exposure to a hot 

 blast the fragments in the first crucible preserved their original con- 

 dition except that they were slightly welded together, while those 

 in the second were fused into a lamellated button. Comptes Rendus. 



Phosphorized Copper and Brass. The peculiar effects of the pres- 

 ence of small portions of phosphorus on the properties of metallic 

 copper have been studied carefully by Mr. Parkes, of England, who 

 has taken out a patent for the application of phosphorus to the im- 

 provement of the working properties of metallic copper. Phosphor- 

 ized copper, as it is termed, possesses an extreme degree of mallea- 

 bility, and may be forged readily even when heated to redness ; it is 

 so ductile that it is capable of being drawn out into tubes, which can 

 be flattened in various directions, or even tied into close knots, with- 



