530 Litelligence and Miscellaneous Articles. 



The irucleus resolves itself into incipient cells in the manner above' 

 described. In tracing this process, it appears that the nucleus, and 

 especially its central pellucid cavity, is the seat of changes which 

 were not to have been expected from the recently advanced doctrine, 

 that the disappearing nucleus has performed its entire office by giving 

 origin at its surface to the membrane of a single cell. It is the 

 mysterious centre of a nucleus which is the point of fecundation ; 

 and the place of origin of two cells constituting the foundation of 

 the new being. The germinal vesicle, as already stated, is the 

 parent cell, which, having given origin to two cells, disappears, 

 each of its successors giving origin to other two, and so on. Per- 

 petuation, however, at this period, consists, not merely in the origia 

 of cells in ceils, but in the origin of cells in the pellucid central 

 part of what had been the nucleus of cells. 



The author shows that neither the germinal vesicle, nor the pel- 

 lucid object in the epithelium- cell, is a cytoblast. He suggests, that 

 the cells into which, according to his observations, the nucleus be- 

 comes resolved, may enter into the formation of secondary deposits 

 — forinstance, spiral fibres; and that they may contribute to the thick- 

 ening which takes place, in some instances, in the cell-membrane. 



The germ of certain plants passes through states so much resem- 

 bling those occurring in the germ of mammiferous animals, that it 

 is not easy to consider them as resulting either from a different 

 fundamental form, or from a process of developement which even in 

 its details is not the same as what has been above described ; the 

 fundamental form in question in Mammalia — and therefore it may 

 be presumed of Man himself — being that which is permanent in the 

 simplest plants, — the single isolated cell. 



LXXXII. Intelligence and Miscellaneous Articles. 



ON THE PRODUCTION OF ELECTROTYPES. BY ALFRED SMEE, 

 ESQ., SURGEON. 



[Illustrat9d by Plate VII.] 



^HE mode of taking copies of medals by the galvanic current* is 

 deservedly occupying much of the public attention, and each is 

 striving to add his mite to the perfection of this elegant and useful 

 process. There are two or three points to which I am desirous of 

 drawing the attention of your readers, as they appear to open a new 

 and important field for investigation for which I have not the time at 

 present. With regard to the precipitation of the copper, I beg leave 

 to submit a modification of a plan first proposed by Mr. Mason, in a 

 paper read before the Electrical Society, but I believe also contem- 

 poraneously used by other persons, that of making copper form the 

 oxygeia side of the battery, which being dissolved is again thrown 



* We learn from the foreign journals, that Prof. Steinheil, of Munich, is ap- 

 plying this process for making a cast in copper, from a composition by the cele- 

 brated sculptor Schwanthauler, representing the labours of Hercules, and con- 

 taining 140 figures. — Edit. 



