TIC 



T 1 N 



The feftion of the afFefted nerve was thought of and 

 tried many years ago in the cure of this difeafe ; and of late 

 years, from a temporary' fuccefs, fome praftitioners have 

 confidently aflerted, that the cure was effeftual and radical ; 

 but more recent experience has deftroyed the validity of 

 fuch aflertions. 



So long back as the year 1768, Veillard publifhed a 

 thefis, in which he decided this queilion in the negative. 

 " Utrum in pertinacibus capitis, facieique doloribus, aliquid 

 prodefTe pofle fectio ramorum nervi quinti paris ?" Now 

 it is not likely, that he (hould have treated this important 

 queftion fuperficially, but that he would rather colleft all 

 the information that at that time could be obtained upon 

 the fubjeft. He mentions two cafes where the difeafe 

 returned after the divifion of the nerves ; and others, in which 

 bad confequences enfued after the operation. Marefchal, 

 about the middle of laft century, operated twice without 

 fuccefs. Pujol was fo convinced of its uncertainty, that he 

 would not venture upon it. He has feen the mufcles 

 paralyfed, and the face diftorted in confequence of the 

 operation. Sabatier relates, that Ritah, furgeon to the 

 king of Poland, performed the operation with fuccefs; 

 but the patient, after being free from the complaint for 

 fome time, was again attacked with his former pains. 



Modern praftice feems alfo to confirm our fcepticifm 

 in the permanent fuccefs of dividing the nerves. We fee that 

 what was at firft fuppofed to be the moft decifive cafe in its 

 favour, the operation performed, and the account of it fo ably 

 recorded by Dr. Haighton, is now not to be relied 

 npon. Mr. A. P. Cooper has frequently performed the 

 operation with fimilar prefent fuccefs, but with what per- 

 manency time only can determine. 



There is a cafe related by Darwin, in the Zoonomia, of 

 a gentleman who firft had the fecond branch of the fifth 

 pair of nerves divided ; then the firft branch ; and thirdly, 

 the remaining third branch. But the patient was not yet 

 relieved. He then had feveral incifions made acrofs the 

 fide of the nofe, and offa nafi, through the mafleter 

 mufcle to the jaw-bone, through the parotid gland. And 

 laftly, fome more twigs from the fecond branch of the 

 fifth pair, paffing into the cheek, and lying between the 

 pterygoideus internus mufcle, and the upper part of the 

 lower jaw. Thefe operations were performed by Mr. 

 Cruikfhank and Mr. Thomas. The patient, it feems, at 

 length efcaped alive and cured. De Haen has divided the 

 fuborbitar nerve, as have alfo Moreau and Guerin, without 

 any bad confequences. For the beft method of operating, 

 fee Dr. Haighton's paper in the medical records. 



It appears then, that as yet we know of no certain and 

 radical cure for this painful affeftion. The feftion of the 

 nerves promifes the faireft ; but when it is had recourfe to, 

 the patient fhould be warned of the poffibility of the 

 complaint returning, and not amufed with the certainty of 

 its being completely cured. Admitting, however, that the 

 difeafe may return in the courfe of a few years, the ope- 

 ration is fo fimple, is attended with fo httle inconvenience or 

 danger, andthe relief in general fo complete andinftantaneous, 

 that there can be httle hefitation on the part of the prac- 

 titioner in reconamending its being performed, when the feat 

 of the difeafe is accurately afcertained. 



Lentin declares, he has had the misfortune to treat, in the 

 courfe of twenty-feven years, fourteen patients attacked with 

 this painful malady, without radically curing one ; and 

 calls upon all praftitioners to make public any means they 

 may have found to fucceed, either in performing a com- 

 plete cure, or even a partial relief of the fymptoms. The 



only remedies from which he experienced any good effefts, 

 were the tinfture of thomapple. Datura Stramonium Lin- 

 aasi, and the fulphureous baths of Meundorf. 



A French writer relates a method of taking nutriment 

 for thofe patients who feel an appetite, but dare not indulge 

 it, on account of the extreme pain ; and that is, to fuck 

 through a fmall tube, as a quill, reed, &c. foup, broth, 

 milk, or any nourifhing fluid, fo gently as not to excite 

 any pain. 



TILE-ORE. See Copper, and Mineralogy, ^d- 

 denda. 



TIN, Crystalltzed, a kind of manufafture faid to have 

 been accidentally difcovered in France by M. Baget, called 

 metallic watering, or moire metallique. It depends upon 

 the aftion of acids, either pure or mixed together, and in 

 different degrees of dilution, on alloys of tin. The variety 

 of defigns refembles mother-of-pearl, and reflefts the 



light in the form of clouds. The procefs is this : 



Firft, diffolve four ounces of muriate of foda in eight 

 ounces of water, and add two ounces of nitric acid.— 

 Second mixture ; eight ounces of water, two ounces of 

 nitric acid, and three ounces of muriatic acid. — Third 

 mixture ; eight ounces of water, two ounces of muriatic 

 acid, and one ounce of fulphuric acid. One of thefe mix- 

 tures is to be poured warm upon a fheet of tinned iron, 

 placed upon a veffel of ftone-ware : it is to be poured on 

 in feparate portions, until the fheet is completely watered ; 

 it is then to be plunged into water, flightly acidulated, and 

 wafhed. The watering obtained by the aftion of thefe 

 different mixtures upon tinned iron, imitates very clofely 

 mother-of-pearl and its refleftions ; but the defigns, al- 

 though varied, are quite accidental. By heating the tinned 

 iron to diSerent degrees of heat, ftars, fern-leaves, and other 

 figures, are produced ; and by pouring one of the above 

 mixtures, cold, upon a plate of tinned iron, at a red heat, 

 a beautiful granular appearance is obtained. Thefe metallic 

 waterings will bear the blow of a mallet, but not of a 

 hammer ; hence the invention may be ufed for emboffed 

 patterns, but not for thofe which are punched. Different 

 colours and Ihades may be given by varnifties, which, when 

 properly pohfhed, will fet off the beauty of the watering. 

 When the tin is upon copper, the crj'ftaUization appear* 

 in the form of radiations or ftars. M. Lewis Felix Vallet 

 obtained a patent for an invention of this kind, upon 

 dehvering the following fpecification, Feb. 5th, 1818. 

 The procefs of giving the new ornamental furface on 

 metals or metalhc compofitions, confifts in employing thofe 

 acids and faline compounds and fubftances which chemically 

 aft upon tin, and which, when employed in the manner to 

 be ftated prefently, give to the metals or metallic compo- 

 fitions to which they are applied the appearance of a cryf- 

 talhne furface varioufly modified. To produce this effeft, 

 the metal or metalhc compofition ought to be previoufly 

 tinned, or covered with a thin coat of tin. If the metal 

 be pure tin, it requires no previous preparation. All 

 greafe remaining on the tinned furface in confequence of 

 tinning is to be taken off with a folution of potafh, foap, or 

 any other alkahne fubftances. The tin or tinned furfaces 

 fhould then be wafhed with pure water, dried and heated 

 to a temperature which the hand can beac When the 

 furface has thus been cleaned and heated, any of the acids 

 which aft upon tin, or the vapours of thofe acids 

 wiU caufe the deCred appearance of cryftallization ; but 1 

 give the preference to the following compofition, which 

 may conveniently be laid over with a brufh or a fponge> 

 Take one part by meafure of fulphuric acid, dilute it with 



five 



