hUelUnence and Miscellaneous Articles. 247 



In respect of the first of these, it is sufficient to say, that Mr. Halli- 

 well offers reasons for believing that the passage itself in Boetius is 

 an interpolation, and therefore of no higher authority than the age 

 of the oldest MS. in which it is found. It also corrects an opinion 

 given by M. Chasles, that the sipos of the earlier MSS. was the 

 same with the celentis, both signifying either the figure or the num- 

 ber nine. Chasles has since found other MSS. which show the 

 correctness of Mr. Halliwell's view, viz. that celentis was alone 

 used to designate nine and sipos the cipher. Into this subject we 

 cannot here enter further, but merely refer to the work itself, and to 

 two notices by Chasles in the Comptes Rendus, May 1838, and Jan. 

 1839, as well as to Vincent's paper in Liouville's Journal de Math. 

 June 1839. These writers ofiFer strong reasons for believing that 

 both the figures used and their local values, had an origin different 

 from, and quite independent of, that commonly assigned to them. 



The notes on early almanacs was first published in the " Com- 

 panion to the Almanac" for 1839. It contains some curious mat- 

 ter, but we would add that the clog-almanacs vary exceedingly 

 in their notation, and that they are very numerous in collections, 

 the Ashmolean containing nearly half a score, most of them in 

 good preservation. The author might also have referred to Hone's 

 Every-day Book for a good account of them. 



In conclusion, we would express our entire approbation of this 

 curious and valuable collection of early treatises on mathematics, 

 and our anxiety to see the author's more extended plan completed. 

 Despoiled as our MS. libraries were by the Vandals of the Reforma- 

 tion, the devoted enthusiasm of collectors has still saved a vast mass 

 from the general wreck ; and we trust that men equally devoted 

 will always be found to estimate their value, and deduce from them 

 the facts of which they contain the most conclusive evidence. Our 

 antiquaries should always recollect that the history of science is the 

 history of the human character and of the state of social and moral 

 life. 



XXXIV. Intelligence and Miscellaneous Articles. 



SEPARATION OF LIME AND MAGNESIA. BY DOBEREINER. 



IF anhydrous chloride of magnesium be heated in the air, it ab- 

 sorbs oxygen and gives off chlorine. This decomposition, that is 

 to say, the conversion of chloride of magnesium into magnesia, is 

 more quick and complete when chlorate of potash is used instead of 

 iiir as an oxidizing agent. This property renders the separation of 

 lime and magnesia very easy. A mixture or compound of these 

 two bodies, dolomite for example, is to be dissolved in hydrochloric 

 acid ; the solution is to be evaporated to dryness ; the residue of the 

 evaporation is to be heated in a platina capsule, till it ceases to 

 yield hydrochloric acid, and then there are to be gradually added to 

 the mass heated to low redness, small portions of chlorate of potash, 

 till the disengagement of chlorine ceases. The residual mass is 

 then a mixture of magnesia, chloride of calcium, and chloride of 



