200 On the Chemical Establishments 



Annexed to the gas-room is a counting-house, behind which a 

 room twenty-two feet square, commonly called the Magnesia' 

 room, is appropriated to the preparation of that article, and also 

 to the manufacture of the most common saline preparations. 



Such are the general arrangement and dimensions of the various 

 buildings connected with or forming part of the chemical labora- 

 tories ; in a detached building there is a steam-engine of eight horse 

 power, which is employed with proper machinery, for grinding, sift- 

 ing, triturating, pounding, and a variety of other operations, which it 

 is not necessary at present particularly to advert to. There are also 

 connected with the establishment, suitable warehouses, shops, and 

 all other requisite conveniencies for carrying on an extensive trade. 

 In the construction of the new laboratory safety is ensured by 

 the whole being fire proof, and it is ventilated by a series of aper- 

 tures in the roof, which may be opened or closed at pleasure. 

 The main chimney is erected in the centre, and has, opening into 

 it below the pavement of the laboratory, four large flues, one of 

 which enters upon each side of its square base. The shaft is one 

 hundred feet high from the foundation, and is accessible in its 

 interior from one of the under-ground flues. The flues of the 

 furnaces which are placed against the walls of the laboratory are 

 each supplied with registers, and open into a common channel, 

 which surrounds the building, terminating in the chimney as al- 

 ready described. Each of the four large flues has also a separate 

 register, which may be more or less closed or opened according 

 to the operations which are going on in the various furnaces con- 

 nected with it. The furnaces thus arranged are, 



A subliming apparatus for benzoic acid. 



A furnace for the preparation of sulphate of mercury. 



A high pressure steam-boiler. 



A reverberatory furnace. 



A sand bath. 



An apparatus for muriatic acid. 



Ditto for nitric acid. 



Ditto for the distillation of hartshorn.. 



A calcining; furnace. 



