BROMINE IN MINERAL WATERS. 
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experiments, and equally coloured, or rather colourless 
glasses of the same size, that the layer of ether might be of 
the same height and breadth. 
In the next place, a series of liquids containing a known 
amount of bromine, was prepared by dissolving in every 
25 grms. of distilled water, from 5 to 50 milligrms. of 
bromine. In this way I formed a series of equally large 
test-tubes of white glass, which contained in the same 
quantity of water (25 grms), 5, 10, 15, 20, 25, 30, 35, 40, 
45 and 50 milligrms. of bromide of potassium. Equal 
quantities of ether, measured in the same glass, were 
added to these solutions, and the tubes immediately closed 
The same vessel which served to measure the ether, 
answered also for the chlorine water, it having been pre- 
viously found by experiment, that more chlorine water 
did not render the ether of the solution containing most 
bromine darker. The addition of the chlorine water to the 
test-glasses, was likewise effected as quickly as possible. 
They were then well shaken; the ether soon collected on 
the surface, and a beautiful, extremely regular scale of 
colours from yellow to brown was obtained — a proof that 
that the solutions might serve as standards for comparison. 
Beyond 50 the comparison becomes more uncertain, 
because the tints of every additional 5 milligrms. of bromide 
of potassium can no longer be well-distinguished on ac- 
count of the dark colour. It is however evident that 5 mil- 
ligrms. bromide of potassium = 3.3 milligrms. bromine, 
dissulved in 25 grms. water, diluted therefore 7600 times, 
exhibit a remarkable reaction, and that the limit of sensi- 
bility is far greater, certainly beyond 20,000 times dilution. 
As soon as the scale of colours had been prepared, the 
glasses filled with mother-leyand ether, which were perfectly 
similar in size and had been previously arranged, were 
shaken with chlorine water, and the tints produced com- 
pared with those of the test-glasses. Each glass contained 
equal volumes of the ley from the different salt-works. 
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