372 iScientific Intelligence. 



Protosulphute of iron, - l.QfiSe 



. manganese, - 0.0260 



Sulphate of zinc, - - 0.0133 



— — lime, - - 0.3705 



■ magnesia, - - 0.1716 



Ammonia alum, - - 0.2126 



Soda alum, - . - 0.4790 



Potash alum, - - 0,0433 



Chloride of aluminum, - - 0.0230 



Silica, - - - 0.1151 



2.5230 

 One of the very few known mineral waters of a similar kind is that at 

 Sandrock, in the Isle of Wight, which is, however, three times as strong 

 as the water of Ronnely, having a spec, gravity of 1007.5 and containing, 

 according to Marcet, in an English pint 



Crystallized sulphate of iron, - . _ 41.4 grains. 

 Sulphate of alumina, which can be obtained in the state of 



crystallized alum, - - - , 31,6 



Crystallized gypsum, (sulphate of lime,) - - 10 1 



Crystallized sulphate of magnesia, - - - 3.6 



■ ' ' ' ■ soda, - - _ 16,0 



Common salt, - - - - _ 4.0 



Silica, ------ .7 



107.4 grains. 

 It is obvious, that in the use of such mineral waters as these, great care 

 must be exercised ; for with such ingredients they may speedily produce 

 serious effects upon those who use them indiscreetly. 



7. Atomic weight of Iodine and Bromine. — Berzelius has lately publish- 

 ed in the Transactions of the Swedish Academy ^ some very careful analyses 

 of the Iodide and Bromide of silver, from which he deduces the followir^ 

 results : — 



Atom of iodine = 789.749 

 Double atom = 1579.498 

 Spec. grav. of gaseous iodine = 8.7078 ^,,. 



Iodic acid consists of Hi'^t^ ''''^'"' 

 ( 24.058 oxygen 



„ 1 • J. '1 e r 99.216 iodine 



Hydnod.cac.dof | o.784 hydrogen 



And its specific gravity by calculation == 4.8883, being only 0.0517 diffe- 

 rent from Guy-Lussac's experimental result : — 



Atom of bromine = 489.15, 



Double atom = 978.3, 



Spec, grav, of gaseous bromine = 5.3934 



xx^^r^- „„:j / 66.177 bromine, 



Bromicacid=|33g2Soxygen, 



