214) Fluidity of Sulphur at Common Temperatures. [1827. 



quickly, that the touching body cannot penetrate its mass. If 

 the smallest morsel of phosphorus is put into contact with a 

 liquefied portion, the latter infallibly solidifies, though it be 

 only a single degree below the limit of temperature necessary ; 

 this does not always happen when the body touching it is hete- 

 3neous. 



Sulphur presented the same phenomena as phosphorus ; 

 fragments of sulphur always produced the crystallization of 

 cold fluid portions. Having withdrawn the bulb of a thermo- 

 meter which had been plunged into sulphur at 120, it came out 

 covered with small globules of sulphur, which remained fluid at 

 60; and having touched these one after another with a thread 

 of glass, they became solid : although several seemed in contact, 

 yet it required that each should be touched separately. A drop 

 of sulphur, which was made to move on the bulb of the thermo- 

 meter by turning the instrument in a horizontal position, did 

 not congeal until nearly at 30 ; and some drops were retained 

 fluid at 15, i. e. 75 of Reaumur below the ordinary point of 

 liquefaction." 



The ' Bulletin Universel ' then proceeds to describe some 

 late and new experiments of M. Bellani, on the expansion in 

 volume of a cold dense solution of sulphate of soda during the 

 solidification of part of the salt in it. The general fact has, 

 however, been long and well known in this country and in 

 France ; and the particular form of experiment described is 

 with us a common lecture illustration. The expansion, as 

 ascertained by M. Bellani, is - 7 of the original volume of 

 fluid. 



According to the ' Bulletin,' M. Bellani also claims, though 

 certainly in a much less decided manner than the above, the 

 principal ideas in a paper which I have published on the exist- 

 ence of a limit to vaporization ; and I referred back to the 

 6 Giornale diFisica'for 1822 (published prior to my paper), 

 for the purpose of rendering justice in this case also. Here, 

 however, the contact of our ideas is so slight, and for so brief 

 a time, that I shall leave the papers in the hands of the public 

 without further remarks. It is rather curious to observe how 

 our thoughts had been simultaneously engaged upon the same 

 subject. Being charged in the ( Bulletin' with quoting an ex- 

 periment from a particular page in M. Bellani's memoir (which 



