1818.] the Commencement of the Year 1817. Part I. 31 



5. Union of Peroxide of Uranium and Carbonate of Potash. 

 — M. Chevreul has observed that the peroxide of uranium unites 

 with carbonate of potash, and forms with it a crystallizable salt. 

 — (Jour, de Phys. lxxxiv. 472.) 



6. Subsulphate of Alumina.— Stromeyer has analyzed the 

 aluminite found some years ago at Newhaven in Sussex, and 

 made at the same time comparative analyses of the aluminite of 

 Halle, and of Marl near Halle. The result of his analyses is as 

 follows : 



Newhaven. Halle. Mar). 



Alumina 29-868 30-263 • . . . . 30-807 



Sulphuric acid . . 23-370 23-365 23-554 



Water 46-762 46-372 45-639 



100-000 100-000 100-000 



It, is obvious that all these are identical in their composition, 

 *nd that they are compounds of 



1 atom alumina 

 3 atoms sulphuric acid 

 13 atoms water 



X. MINERAL WATERS. 



1. Mineral Spring ofCaldas de Rainha. — This is a hot spring, 

 about 40 miles north of Lisbon, which has been long celebrated 

 for its medicinal properties. The water contains sulphureted 

 hydrogen, to which it probably owes most of its virtues. By 

 Mr. Rennie's account, the country is red sand lying over coal. 

 It is probably, therefore, similar to Warwickshire, and that 

 large tract in the middle of England which consists of what may 

 be called new red sandstone. Dr. Withering subjected the water 

 to an imperfect analysis in, 1795. He found its temperature 94°. 

 One hundred and twenty-eight ounces of it yielded the following 

 constituents : 



Fixed air _<. oz. measure 



Hepatic air 6± oz. measure 



Carbonate of lime 3-i gr. 



Ferrum hepaticum 2-i- gr. 



Alumina 1 3. 



Silica Of 



Magnesian salt 64 



Selenitic salt 44 



Common salt 148 



264 



Mr. Rennie found its specific gravity 1-0058 ; 16 ounces of it 

 being evaporated to dryness, left 24 grains of dry salts, which 

 consisted of 



