Preparation of Borium. — Herculanean Manuscripts'. 3S9 



6rary and billiard-room of this splendid mansion in particular, 

 exhibit a most pleasing and brilliant scene when thus liglited ; 

 and Mr. Potts has added to the _^eneral cflect by the introduc- 

 tion of an efficient system of ventilation, thus precluding all pos- 

 sibility of any disagreeable effect. The establishment from 

 which the gas is supplied is situated at Bankside, and is under 

 the direction of Messrs. Monro and Co. Tl'.e premises are the 

 most roomy that have been hitherto fitted up as a gas-light ma- 

 imfactory, and the whole arrangements of furnaces, retorts, and 

 gasometers have been made upon the most correct and scientific 

 principles. The utmost regularity is preserved in the various 

 <!epartjnents of the works, and not the slightest accident has oc- 

 curred since their erection. 



I'RKPARATION OF EORTUM. 



M. Dobereiner has published a new process for extracting 

 borium from borax. — After melting the borax and reducing it 

 to a fine powder, one-tenth of its weight of lampblack is added; 

 this mixture is put into a gunbarrel, one end of which is closed, 

 and to the other is affixed a tube for receiving the gas, and the 

 gunbarrel is then kept at a white heat during two hours. Much 

 of the gaseous oxide of carbon is disengaged; and when the 

 process is finished, there remains in the tube a compact mass of 

 a blackisb-grav colour, wliich is reduced to pov.'der, and which, 

 after being washed several times with boiling water and once 

 with hydrochloric acid, yields a pulverulent izrcenisli-blacl: sub- 

 stance sin)ilar to borium, except that it is still mixed with a lit- 

 tle charcoal. M. Dobereiner tiriuks that the charcoal begins 

 by reduciug the soda, and that afterwards it is the sodium which 

 decomposes the boracic acid: consequently, he concludes that 

 a greater cpiantity of borium might be obtained, if to the borax 

 half its weight of soda or of potash wej-e added, and a (juantiiy 

 of charcoal double of that which is here mentioned. 



Hr'RC.nr.ANEAN MAMISCRIP1S. 



Messrs. Tyrwhitt and Hayter having been employed to unrol, 

 if |)0ssible, the fkrculaiieum MSS. belonging to the InstifUe 

 of France, by means of a new process, the Institute has appoinU'd 

 Messrs. \'iscoiiti, Quatremere de Quincy, Ijoissoiiade, and Kaoul- 

 Rochette, to superintend and assist in the operation. 



To Mr. THIolIi. 

 StR, — Being engaged in a baking business requiring a con- 

 siderable supply of yeast, and not being at all times able to ob- 

 tain a sufficient supply, I should consider myscll inu< h olilgtd 

 if any of vour weil-informed correspondents would be pleased 

 B b 3 to 



