S22 Professor Forbes's Account of' 



much lower a temperature, are points of which I can offer no 

 elucidation. 



Products of the Spring, — These are gaseous and mineral. 

 The gas consists, according to Kastner, of almost pure carbonic 

 acid, there being also a trace of azote. A pound of water is 

 combined with 30^ French cubic inches of gas. But this gives 

 no conception of the quantity which is evolved wholly uncom- 

 bined. I have in vain thought of a plan to estimate roughly 

 its amount. Even the first few minutes of returning action of 

 the spring in its feeblest state after ebb, are sufficient to fill the 

 entire shaft (containing 920 cubic feet) with gas, and the tur- 

 bulence of its disengagement during full action I have already 

 attempted to describe. 



The carbonic acid gas has been applied as an external sti- 

 mulant to the eyes, ears, and the whole body. For this pur- 

 pose, a large inverted iron funneL 5 or 6 feet in diameter, is 

 dropped by a pulley, so as to float on the surface of the water, 

 and the gas collected under it is conveyed by means of a flexi- 

 ble tube into a neighbouring building, where gas baths are 

 regularly administered. When it is to be generally applied, it 

 is introduced into a wooden tub, in which the patient (clothed 

 as usual) is seated, and, from its density, it soon fills the tub, 

 and flows over upon the floor, through which it sinks by venti- 

 lating apertures properly distributed. Its effect is exciting 

 and agreeably warm over the whole body, and is found to be 

 useful in cases of local relaxation of the vascular system. 



The mineral discharge of the spring consists of from S5 to 

 40 Bavarian cubic feet of brine per minute. On the 24th of 

 August, I found it to be about 37 cubic feet, but the experi- 

 ment did not admit of great accuracy. Its specific gravity that 

 day was 1.0157, at a temperature (as well as I recollect) of 

 16° Reaumur, which is nearly its mean value. Both the quan- 

 tity and quality are regularly measured and registered by the 

 Government authorities presiding over the salt-works. The 

 sp. gr., I was informed varies from 1.0164 to 1.0130, and lower 

 when the water of the Saal gets in. I was likewise assured 

 that it is not densest after warm weather, but rather in a damp 

 season, and when the Saal is high. Here follows Kastner's 



