S20 Professor Forbes's Account of 



On these observations the following remarks present them- 

 selves. (1.) Whilst the mean of all the temperatures would 

 not differ materially from the temperature of the air observed 

 by Dr Balling, a discriminating examination of them would 

 lead us to place the mean temperature of the ground at 

 Kissingen considerably lower. For, though in the months 

 of July and August, deep springs may shew a temperature 

 too low, not having yet reached their ascending mean, the 

 majority of surface-springs will then be too high.* (2.) We 

 find, in general, but little difference between the tempera- 

 tures in the first tables and those in the second, the circum- 

 stance of mineralization and discharge of carbonic acid not 

 appearing to accompany a materially higher temperature, as it 

 frequently does. 



But when we consider how these observations bear upon the 

 point we have specially in view, the relative temperature of the 

 great brine spring, the result is very interesting. Scarcely in 

 a single instance, besides the Schonborn Quelle (of which, as we 

 have seen, the depth is 550 feet), does the temperature reach 

 52*, whilst that of the Runde Brunnen is QB". Were we to at- 

 tribute the excess of from 13° to 15°, to the depth of the arte- 

 sian well solely, and thence compute the rate of increase in 

 descending, we should greatly err ; for, in the first place, the 

 water of the far deeper Schonborn Quelle has an excess of only 

 2° or 3° (owing partly, no doubt, to the feebleness of its flow), 

 and in the next, it is quite certain that the temperature of the 

 Runde Brunnen is wholly independent of the particular depth of 

 its bore. It is in this respect that the journal of the work 

 already given (page 310), is so interesting. We trace the gradual 

 accumulation of the water ; we find that the periodical charac- 

 ter of the spring commenced when the depth was 156 feet ; 

 that we have no right to conclude that the chief volume of 

 water comes from the bottom, for no sudden increase was ob- 

 served ; the augmentation of flow was gradual as the water 



• Perhaps, however, the discrepancy is really owing to the sheltered 

 situation of Kissingen (as the springs in its immediate neighbourhood have 

 almost the temperature of the air), whilst the surrounding country in which 

 many of the springs above mentioned are found, is, though not very ele- 

 Tated, comparatively bleak and exposed. 



