(to the editor of the west coast times.)

West Coast Times, Issue 379, 10 December 1866, Page 3

(to the editor of the west coast times.)

Sie — I obsei-ved in the West Coast Times of tlie Clh inst. a letter signed by Mr T. E. Procter, relative to my solvent for gold. Mr Procter is a perfect stranger to me, and draws me into controversy reluctantly. lam ;i bt ranger to him, consequently I am ignorant as to what qualifications he may possess. Whatever his attainments are, I am prepared to prove the fallacy of his theory. Ido not profess to have discovered chlorine ; it was announced, about fifty years since, as a new body, creating a wondrous change in the arts and manufactures, especially for bleaching purposos. Mr Procter is coned as to one method wleroby it may bo procured; he says, if equal parts of black oxide of manganese and common salt bo converted into a pasfe by tho admixture of sulphuric acid, then placed in a retort, applying heat that chlorine v> ill evolve ; granted," but it will evolve without applying heat in the early stage, but where would be the manipulator? Almost instantaneous death would ensue from inhaling tlie gas. An expert introduce the compound into a retort, and by the aid of a long stem funnel provided with two stop cock 3, introduce the acid in vacuo. Mr Procter then slates, that if pieces of gold are thrown into one of the bottles in the pneumatic trough, the metal will take fire, and by combining with the chlorine form a chloride of gold. In theory it may pas.? current, but practically, where is tho man who would risk the consequence ? I am well aware thai it is chlorine that dissolves the gold — that it is the active agent for dissolving gold in aqua regia. I do not attempt to disguise tho agent I employ ; it would bo a folly to attempt it. The odour speaks for itself. What I claim is the origiual idea of using this agent as a solvent for gold. I promulgated it in Melbourne in 1857 — published it in London 13th August, 1859, in the " Australian and New Zealand Gazette."

Mr Procter states that by mixing one part nitric and two hydro-chloric acids that he forms '" aqua regia." Admitted, but any tyro ought to know that applying heat to either of the acids mentioned by him will evolve their respective gases ; combined, they throw oIT chlorine, " but not without heat."

Presuming Mr Procter is familiar with aqua regia, and keeps it in the general atmosphere, does it lose its power ? Certainly not, and by introducing gold it does not throw off gas, unless heated,, although a sirong action is seen and the gold becomes dissolved. Perhaps Mr Procter can inform me what effect ether will have open this compound, Mr Procter slates that aqua regia heated produces pure chlorine, and oy continuing the heal the evolution of chlorine ceases, and the residual liquid is a solution of hydrochloric and nitrous acids;" which are incapable of dissolving gold, and that hydrochloric and nitric acids decompose each other, tlirowing off chlorine, whilst hydrochloric and nitrous acid may be heated together without mutual decomposition. This logic, shows his ignorance of the ehcmieul action of nitric and nitrous acids. Nitric speedily becomes nitrous, by the action of the atmosphere, but nitrous will not become nitric. Mr Procter infers that the powers of hydrochloric and nitric acid in dissolving {•old is owing to the liberation of chlorine. For his better information I inform him that the strong atlinity of chlorine for gold forms a chloride of gold, absorbing the gas. He ought to be well aw are that neither of tho two acids he mentions will act upon gold seperately — in conjunction, readily. I do not confine myself' to (lv« proportional* announced by Mr Procter, it is frequently 3 and -1 to 1. Mr Procti-r brings his loiter towards conclusion, staling that it was known to chemists many yearo ago, aud that my process will bo found an exceedingly inconvenient and unprofitable method of extracting gold from tho soil. In the first place, the solvent prepared by me (Mr Eobcrts), contains 97? por cont. of water, which leaves room for only two and a -half per cciii. of the. solvent : but he Joes not define what that solvent is. He says, 2\ per oenf. of solvent. I quote 100 per cent, of solvent, whereof 97 i per cent, is water. I can prepare with tho aid of four men and a 300 gallon cask, 300 gallons in half an hour. I can eliminate tho solvent from several compound salts, and upon a largo scale prepare it in England for one farthing a gallon, from ihe very best of chemicals. One gallon will dissolve an ounce of gold without the aid of fire. Had Mr Procter sought information from me I would have given him practical demonstration thereby tho production shown in the W£ST Coast Times, calculated to mislead the public generally. Yours truly, WILLIAM EOBEETri.

Census Statistics of this United States. — A valuablo statistical table, exhibiting the rate of increase in the population of tho different Stales in tho Union ainco the census of 1860, is now in course of preparation at Ibe Departniont of tho Interior. Tho census of 1865 has been received by tho department from seven States, and tho increase of population, even during tho existenco of the war, in which tho mortality was unusually largo, is as follows : Minnesota, forty per ceufc. ; Illinois, twonty-&ix por cent. ; Wisconsin, twelve por cent.; lowa, twolvo per cent.; Michigan, seven and five-tenths per cent. ; Rhode Island, four per cent. ; Massachusetts, three per cent. TTakiug the general average of this increase — thirteen and ono-hulf per cent. — as a fair xoprescntuiioa of the ratio of increase in tho other .Suites, the Census Bureau estimates that the population of the United States and Territories has iucroa&od from 3J,443,321— the number found by tho census of 1860— to 35,500,000.