90 



KNOWLEDGE • 



[Aug. 1, 1884. 



and not yet publibhed to the world) is that of injecting 

 through the optic foramen, by the introduction of a long 

 subcutaneous needle into the cavity of the cranium from 

 behind the eyeball. This method, -which will no doubt 

 supersede all others, was discovered rather by accident than 

 direct experiment, and dates from researches conducted by 

 Dr. Richardson on the best modes of restoring animation 

 after sudden dissolution from chloroform and other lethal 

 substances. Thus, in original work it often happens that, 

 in carrying out a design which has been most carefully 

 projected, the origin<<l intention is not consummated, but 

 some other result which was never thouglit of ; and thus 

 Columbus, in search of the golden lands of Marco Polo, 

 accidentally lighted on the continent of America. It will 

 be noted that in the modern system nothing of the ancient 

 survives. There is no exenteration, no steeping in palm- 

 wine, no filling of the cavities with myrrh and cassia, no 

 swathing with bandages a thousand yards long, which, 

 nowadays, the pilfering Bedouin use for clothes and sell 

 for paper. Nor is there any need for the -opaiyyin-i]c, that 

 low-caste official, whose hateful duty it was to make the 

 first incision, and who must needs have been as nimble of 

 foot as he was quick of hand, since (all in Egypt being 

 held in abomination who mutilated the dead), on the com- 

 pletion of the operation he had to make the best of his 

 way into the country, pursued with sticks, stones, and 

 curses. There, in a date -grove, he panted till the storm 

 had blown over. He was the original, they say, of the 

 familiar phrase to cut and ruii. Nor in our civilisation is 

 the attendant expense in any degree as great. It ranges 

 from 20 to .50 gs., varying with the circumstances of the sur- 

 vivors. Mr. Whiteley, whom we have consulted, will under- 

 take an adult for £42. 10.«., while the best workmanship of 

 the Nile could not be secured for less than a talent, 

 .£243. 153. In a sketch of this rapid character, in which 

 we have striven to avoid as far as possible all unpleasant 

 details and tiresome technicalities, there is necessarily 

 much omitted that is historically interesting, though mote 

 perhaps to the student — if any such there be — than to the 

 general reader. There is that Guinea tribe, for instance, 

 who by some mysterious process reduce their relatives to 

 a liquid condition and drink them down ; and so, perhaps, 

 have givf n rise to the saying that the society of certain indi- 

 viduals is refreshing. Tliere is the desiccation practised by 

 the Palmeritans, who put their friends aside in a chamber 

 underground to dry, where they may still be seen in all the 

 dreadful contortions of the process. There is Marshall's 

 system of puncturing the surface of the body and brushing 

 t over with acetic acid of the specific gravity of 1-048 — 

 "two days' application in this way will beautify any sub- 

 ject." There is the tadpole arrangement (though we cannot 

 be sure that this has ever been applied to the human frame) 

 by which a sul)ject, suspended in water and left free to be 

 acted upon by the suction-mouths of these little creatures, is 

 in a short time stripped of aU those parts which would other- 

 ■wise decay. There are the natural mummies of the sands and 

 of the bogs of Ireland and Scotland, and the lost travellers 

 of the Alps, in a sense preserved by cold : and, not to be 

 tedious, there is that buried secret of the Florentine physi- 

 cian Segato, by the exercise of which he could reduce the 

 dead. Medusa-like, to stone. By this process of Segato's 

 the head of the patriot Mazzini was, we believe, successfully 

 treated, and still, no doubt, is in existence, the cherished 

 treasure and pride of some Italian municipality; and though, 

 as a means of preserving the dead, the method was never 

 widely known or popular, yet it found its way into England ; 

 for we have been told, indeed, by the greatest living autho- 

 rity on mummies, that, many years ago, when present at a 

 conversazione in London where several specimens of the 



Florentine's art were exhibited, he disc-overed among them 

 a table inlaid, apparently with strange and curious marbles, 

 but which on closer inspection resolved themselves into the 

 interiors of dead friends. — Cornhill Mayazine. 



ELECTRO-PLATIXG. 



IX. 



By W. Slisgo. 



IT frequently happens that large statues are taken by the 

 electrotyping process. Sometimes the object in -view 

 may be simply to copy one sculptured in marble, ic. ; at 

 other times a bronze statue may be the thing desired. 



To attain such an object, one of two processes is generally 

 adopted. 



In the case of a plaster figure, the surface of the statue 

 is saturated with linseed oil, and then allowed to dry. 

 When quite dry, it is thoroughly plumbagoed, the surface 

 presenting a uniform polished appeai-ance. It is then 

 placed in the solution, and a deposit is taken, the thickness 

 varying with the size of the work. It must be sufficiently 

 strong to be used as hereafter described. As intimated in 

 the previous article, care is taken to insure a good 

 deposit in the hollows by inserting small anodes in 

 them, and keeping the main anode either a consider- 

 able distance away, or out of the bath altogether. 

 Where this course is rendered impracticable by pecu- 

 liarities or eccentricities in the shape of the mould, the 

 anode is for a time placed at some distance from the 

 cathode. This plan is in the main objectionable, and it is 

 often found better to employ a current of high electro- 

 motive force at the commencement of the action. This, 

 when using liatteries, is easily done by introducing one or 

 two extra cells " in series," and withdrawing them as soon 

 as the mould has received a copper deposit all over it. 

 When the coating has attained a sufficient thickness, the 

 mould is withdrawn and the metal cut in halves, 

 or in other convenient sections. The plaster is then 

 sawn through, and afterwards extracted piece by 

 piece until the whole internal copper surface is free. 

 In this process the plaster model is thus sacri- 

 ficed. When thoroughly cleaned, copper wires are 

 soldered or otherwise attached to the external surfaces of 

 the various copper sections. These surfaces are then 

 " stopped off" with gutta-percha varnish, that is to say^ 

 they are coated with the varnish consisting of gutta-percha 

 dissolved in bisulphide of carbon (CS^) to insulate them, 

 and so prevent deposition upon them when placed subse- 

 quently in the electrolytic bath. When thus pro-i-ided 

 externally, the internal surfaces are treated with ttupen- 

 tine, exposed to sulphuretted hydrogen fumes, or dipped in 

 a weak solution of sulphide of potassium. The object of 

 this treatment is, while it allows deposition to go on, to 

 prevent the adhesion of such deposit to the original copper 

 form. The copper sections having been treated in this 

 manner, are again placed in the bath, and a good, substan- 

 tial deposit is taken. When these positive sections are 

 sufficiently thick, they are withdrawn from the solution, 

 together with their previously-taken negative films, which 

 are carefully stripped off, exposing clean and clear surfaces 

 bearing an impression of every feature pertaining to the 

 original plaster model. The sections are then trimmed, 

 any superfluous pieces of metal being clipped or filed away. 

 After this they are fitted and soldered together, and the 

 joints bronzed over. 



This method is largely employed where the work is 



