Rev. J. B. Eramett on Capillary Attraction. 1 1 7 



use of, inflammable liquids, i. e. those which tend to the nega- 

 tive pole, are least elevated : however, I dare not yet assert 

 this as a fact. I have been some time engaged in a series ot 

 experiments on this subject, which have led to very curious 

 results, and which I am continuing at present: they will be 

 re^rularly communicated to the Philosophical Magazine ; and 

 win, I hope, develope the laws obeyed by this lorce. A full 

 examination of its phfenomena will greatly tend to elucidate 

 those of chemical action. 



It is stated, I believe, in all books of philosophy, that the 

 altitude of the column raised by the power of capillary attrac- 

 tion is not affected by changes of temperature. 1 find that it 

 is depressed by heat and elevated by cold. If a capillary tube 

 be immersed in boiling water, the column cools as it rises, and 

 consequently no effect can be expected. I therefore employ 

 the following method : i • • 



The capillary tube (about i-if o to jUo of ^" '"'^^,.'" .'"" 

 ternal diameter) is placed in a test tube, containing the liquid : 

 the tube is filled ; and the fluid allowed to fall, till it becomes 

 stationary. When water is used, it is pure ; it is also boiled, 

 to expel the air it contains, immediately before the experiment 

 is made. The following are some of the results : 



Inches. Tenths. 

 Altitude of the column of cold water 2 4-5 



Ditto boiling 2 0-5 mean of 3 exp. 



Depression caused by heating the water 4'0 



Proof-spirit, cold 9*5 



Ditto, boiling 8-75 1st exp. 



Ditto, ditto , . . 8-75 2d ditto 



Depression by heating 



Altitude of column of water at 70"^ 

 Altitude by immersion in snow . 

 Altitude when boiling 



•75 



2 1 



2 2-5 rise 1-5 tenth. 



1 8 



Difference between the extremes 



Weak sulphuric acid, which had "^ 

 been kept in a badly stopped V . 

 bottle lor three years, — cold j 



Heated nearly to ebullition . 



Cooled till it was rather warm 



Boilinjr rapidly 



4-5 



1 

 2 0-5 



.'. maximum 

 depression f^^. 



Quite cold 2 0-5J 



The 



