58 ALUMINOUS CHALYBEATE SPRING IN I. OF WIGHT. 



5. It appeared probable from experiment K, that the 

 water contained a small quantity of muriatic acid. 



6. The change produced in experiment B, on the infu- 

 sion of Brazil-wood, appeared at first ambiguous; it could 

 not be owing to the prevalence of an alkaii or carbonated, 

 earth, since the water turned litmus red, and since the pre- 

 sence of carbonated earths had been disproved by other re- 

 sults. But having found by comparative trials, that solu- 

 tions of sulphate of iron changed paper stained with infusions 

 of Brazil-wood to a black, or at least intensely dark violet 

 colour, and that solutions of alum turned it crimson 

 observing that a mixture of these solutions produced a dark 

 purple hue, the appearance in question was easily explained. 



7. The result of experiment L indicated the presence of 

 su'phuricacid. 



8. Upon the whole, and from a review of the foregoing- 

 experiments, the substances which, at this early stage of the 

 analysis, the water appeared most likely to contain, were 

 sulphate of iron, sulphate of alumine, sulphate of lime, and 

 a small quantity of muriatic salts. Some sulphate of mag- 

 nesia, and some alkaline sulphates, might possibly be con- 

 tained in the water, though their presence could not be 

 satisfactorily ascertained by these preliminary experiments. 



Sect. V. Gaseous contents of the Water, 



G&coa* con- A^ quantity of the water measuring ten cubic inches, be- 

 ^, 01 1 e ing boiled briskly over mercury, the gas given out, together 

 with the air contained in the apparatus, was received in a 

 graduated tube ; on admitting caustic alkali into the tube, 

 one tenth of a cubic inch of gas was absorbed. It appears 

 therefore, that one hundred cubic inches of the water contain 

 one cubic inch of carbonic acid gas, which is equivalent to 

 about three tenths of a cubic inch to each pint. The water 

 Was uncorked at the moment of being examined, but I had 

 not an opportunity of ascertaining the quantity of gas. 



Sect. VI. Evaporation of the Water, and Estimation of the 

 Quantity of solid Ingredients. 



Quantity of 1. Sixteen ounces of the water by measure, being evapo- 

 *qli4 mgredi-^ rate( j <j wn to a soft mass over a lamp, and afterward desic- 

 cated 



