182 Scientific Jntelligence — Geology. 



chlorures of soda and magnesia, the sulphates of soda, lime, mag- 

 nesia and potassa, diminish relatively to the total mass of the salts 

 as we descend from the summits, and form nearly from 25 to 30 in 

 the 100 of the dissolved salts; the sulphates from 24 to 31 in the 

 100; the carbonates from 36 to 47 in the 100; 3c/, That in the 

 anthraxiferous formations, the sulphates of soda, lime, and mag- 

 nesia, exist in greater absolute quantities than in the talcose forma- 

 tions, and represent from 18 to 37 in the 100. This proportion of 

 sulphates is explained by the nature of this formation, composed as 

 it is of sandstones and argillo-calcareous slates, very rich in pyrites, 

 gypsums, and dolomites ; the chlorures do not here exceed from 

 10 to 16 in the 100; 4«/i, That in the cretaceous formations, the 

 chlorures and sulphates diminish considerably, to the gain of the 

 carbonate of lime and carbonate of magnesia, in the waters which 

 flow over the dolomitic limestones. M. Grange makes the follow- 

 ing remarks on this subject : — 



'* It appears to me that these results ought to be of interest, not 

 only to chemists and geologists, but also to physiologists, physicians, 

 and agriculturists. 



" It is now an opinion generally established, that our household 

 waters perform an important part in nutrition, by furnishing sub- 

 stances necessary to the wants of the economy, and that the latter 

 does not always find a sufficient quantity of them in the ordinary 

 aliments; such is the case with the carbonate of lime. But these 

 waters may contain, sometimes useful mineral principles, at other 

 times deleterious ones, and it is to these deleterious principles that 

 the people themselves, and observers, ascribe the development of 

 goitre, cretinism, and rachitism." 



*• I have given a rapid sketch, in my work, of the opinions ex- 

 pressed as to the probable cause of goitre and rachitism, and have 

 shewn that none of these theories can explain the facts. My ana- 

 lysis having indicated the presence of a considerable quantity of 

 magnesia, from 10 to 15 in the 100 of the total amount of salts, 

 in all the waters of the villages and valleys where goitre and cre- 

 tinism are endemic; and observing that these analyses, made in three 

 different formations, — the talcose, anthraxiferous, and cretaceous, — 

 may explain the development of the endemic affections by the pre- 

 sence of the salts of magnesia, I have carefully inquired whether 

 magnesia rocks existed in the High Alps, Switzerland, Piedmont, 

 the Vosges, Pyrenees, and in all other places where these maladies 

 prevailed; and, in fact, talcose, gypseous or dolomitic rocks, and 

 ophites, were to be found wherever goitres or cretins appeared. 

 M. Elic de Beaumont, in his Memoirs, so rich in geological obser- 

 vations, brings forward many facts which support my opinion. M. 

 Boussingault also states, that he collected a series of gypseous or dolo- 

 mitic rocks in the provinces of the Andes, where he observed goicres. 

 M. Darwin, in his work on South America, is so struck with the 



