The quantity softened is 21/4 million gallons per 24 hours, but the present plant can deal with 21/2 million gallons, and the buildings are erected for 31/2 million gallons, additional filters and lime producing tanks being only required to deal with the increased quantity.  The costs of the softening works was L10,394, of which L7,844 was for the softening machinery and plant and L2,550 for the reservoir, buildings, etc.

The working expenses, including lime, labor, cloths, general repairs, and steam, is stated to be 0.225d. per 1,000 gallons, the labor required being only two men, one on the day and the other on the night shift, with an occasional man to assist.

The hardness of the Southampton water on Clark’s scale is 18 deg. of total hardness, and this is reduced down to 6 deg. or 8 deg. by this process.—­Chem.  Tr.  Jour.

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A NEW LABORATORY PROCESS FOR PREPARING HYDROBROMIC ACID.

By G.S.  NEWTH.

This method is a synthetical one, and consists in passing a stream of hydrogen and bromine vapor over a spiral of platinum wire heated to bright redness by means of an electric current.  A glass tube, about 7 inches long and 5/8 of an inch bore, is fitted at each end with a cork carrying a short straight piece of small tube; through each cork is also fixed a stout wire, and these two wires are joined by means of a short spiral of platinum wire, the spiral being about 1 inch long.  One end of this apparatus is connected to a small wash bottle containing bromine, through which a stream of hydrogen can be bubbled.  The other end is attached to a tube dipping into a vessel of water for the absorption of the gas, or, if a large quantity of the solution is required, to a series of Woulf’s bottles containing water.  Hydrogen is first slowly passed through the tube until the air is displaced, when the platinum spiral is heated to bright redness by the passage of a suitable electric current.  Complete combination takes place in contact with the hot wire, and the color imparted to the ingoing gases by the bromine vapor is entirely removed, and the contents of the tube beyond the platinum are perfectly colorless.  The vessel containing the bromine may be heated to a temperature of about 60 deg.  C. in a water bath, at which temperature the hydrogen will be mixed with nearly the requisite amount of bromine to combine with the whole of it.  So long as even a slight excess of hydrogen is passing, which is readily seen by the escape of bubbles through the water in the absorbing vessels, the issuing hydrobromic acid will remain perfectly colorless, and therefore free from bromine; so that it is not necessary to adopt any of the usual methods for scrubbing the gas through vessels containing phosphorus.  When the operation is proceeding very rapidly a lambent flame occasionally appears in the tube just before the platinum wire,