240 ANNUAL OF SCIENTIFIC DISCOVERY. 



^ 

 any freshly-precipitated and well- washed oxide of iron in a solution of 



sugar ; and almost equally unsuccessful was the attempt to do so when 

 the oxide was liberated by means of potash in the presence of sugar 

 itself. It was found that under all circumstances of dilution or quality 

 of the sugar solution, iron was attacked ; the presence of zinc in con- 

 tact with the iron did not prevent its being acted upon ; nor was there 

 any marked difference when the salts of sea-water, or the nitrates 

 sulphates, or chlorides of the alkalies were added to the solution. No 

 other ordinary metal was found to be so easily acted upon as iron. 

 Copper was very little affected by the sugar. Lead was slowly at- 

 tacked, indications of the presence of its oxide in solution being ob- 

 tained after three day's exposure. Tin appeared to give the binoxide. 

 Zinc was little affected when alone ; it seemed to be dissolved more 

 quickly when in contact with iron. It is doubtful whether mercury 

 was touched by the sugar solution ; silver certainly was not. t The 

 author regretted that his experiments did not suggest any method by 

 which the corrosion of iron ships by sugar cargoes might be prevented. 

 They showed rather the strong disposition to combine that there is be- 

 tween the two substances ; and how a small quantity of sugar may eat 

 continuously into a large sheet of iron. The attention of chemists 

 was especially drawn to the fact that the iron enters into combination 

 with the organic matter not when it has already been oxidized, but 

 only when in a metallic condition, rendering the action, as would be 

 imagined, more complicated. 



HIGH TEMPERATURE PROCURED FROM CARBON. 



The following communication has been made to the French Acade- 

 my by M. Deville. It is well known that near the tuyeres of blast 

 furnaces, a very elevated temperature is developed, which M. Eblemen 

 considers to be equal to the melting point of platinum. Some experi- 

 ments made in the course of an investigation altogether different, have 

 led me to believe that the heat developed during the combustion of 

 carbon, is capable of producing effects much more energetic and com- 

 parable with those obtained by means of a mixture of hydrogen and 

 oxygen. Thus, by a suitable arrangement of the furnace, and with 

 the proper kind of carbon, it is possible to melt and even to volatalize 

 platinum and to melt pure silica. These results, and the simplicity of 

 the means by which they may be obtained, have convinced me that 

 they will become useful to the chemist and manufacturer. I have 

 therefore decided upon submitting to the Academy, the details of the 

 operation, which, I trust, will not be found unworthy of attention. 

 The apparatus which I employ, is a simple furnace, 30 centimetres 

 high, and 18 centimetres diameter, supported on a plate of cast iron 

 pierced with holes, arranged in a circle 5 centimetres from the centre. 

 This is placed in connection with the bellows of a portable forge. The 

 best kind of crucibles melt down at the temperature in question, to a 

 perfectly liquid glass, and for a substitute I was obliged to have re- 

 course to pieces of well burnt lime, which may easily be brought into 



