198 M. R. Bunsen on the Laio of Absorption of Gases. 



escape in small bubbles from tbe water wben a vessel filled at 

 the spring is allowed to stand. By agitation the equilibrium is 

 restored in a few moments, and the gas dissolved in the water 

 reduced to its normal amount. By similar considerations, it is 

 easy to sec that many of the statements, with regard to the 

 amount of carbonic acid contained in springs, must be false. 

 Thus, for instance, the amount of carbonic acid contained in the 

 " Fiirsten Quelle " in Imnau, is given by Sigwart to be 2500 

 cubic centimetres in the litre. Under the mean pressure and 

 at the temperature of the spring 6 0, 3 C, the water can, however, 

 according to the law of absorption, only contain 1373*2* cubic 

 centimetres after the equilibrium has been established. The 

 amount of gas, 2500, requires a pressure of l m, 3836 of mercury, 

 or a column of water of 8 m- 449, to be added to the mean baro- 

 metric pressure. As, however, it is impossible to suppose that 

 the Imnau spring rises under the pressure of a column of water 

 at least 25 feet high, and as a saturation of nearly double the 

 amount of gas is as improbable, we are compelled to assume 

 that Sigwart's experiments are based upon error. The falsity 

 of many other similar statements may thus be easily shown. 



The relations which are found to exist between the free and 

 absorbed gases of a spring by means of the law of absorption, 

 give a fixed starting-point from which to estimate the influence 

 which an amount of nitrogen in the free gas in a spring exerts 

 upon the quantity of carbonic acid dissolved in the water. The 

 second and third columns of the following table, calculated from 

 the preceding formula?, show the per-centage amount of carbonic 

 acid and nitrogen in the absorbed gas for the corresponding per- 

 centages of nitrogen in the free gas given in the first column. 

 The temperature of the water is supposed to be 15 G, 1 C. 



* The small amount of solid constituents contained in the water (not 

 more than 9 grains ia a pound) cannot appreciably alter the absorption- 

 coefficients, certainly not increase them. 



