Tn.VNSACTIONS OF SECTION F. 



685 



It will also be seen that tlie dry assay is uniformly too low, and always con- 

 siderably short of the truth. This is proved not only by its difference from the wet 

 assay, but also by actual results obtained by smelting, where the surplus copper 

 forms a very considerable portion of the profit. But the wet assay is proved to be 

 the true assay by results obtained on the large scale when my process of extraction 

 is used, and the precipitate produced refined. I give the i-esults from four different 

 works, in situations far distant from each other, and all for the same year. The 

 works are placed in the order of their erection, D being the most recent and the 

 most perfect in construction. 



These results were obtained ten years ago ; but with increased experience and 

 better plant the produce by tlie wet assay has been obtained with great regularity to 

 within the .second place of decimals. The results shown in the above table prove con- 

 c-lu.sively that the dry assay is not within 33 per cent, of the truth ; for these four 

 works in one year, by the treatment of nearly 56,000 tons of ore, actually refined 

 and sold no less than 561 tons of copper more than the dry assay declared existed in 

 the ore. There can be no mistake about a reality of this kind ; and what are we to 

 .say in favour of a system which is so misleading ? In any other branch of business 

 such proved inaccuracies would never be tolerated a moment ; and the worst of it 

 is, that the lower the percentage of copper in the ore the greater the proportional 

 difference. By reference to tables supplied by Messrs. Mason & Barry, we see that 

 wlieu the dry a,ssay says the ore contains 1 per cent, copper, the wet assay says at 

 least 2 per cent. ; so that if these four works had been working ores of what the 

 dry assay called 1 per cent., they would most assuredly have got 2 per cent, out, or 

 100 per cent, surplus. A very amusing instance of the utter uselessness of the dry 

 assay for poor ores was shown in the case of the Alderley Edge ores, which were 

 a ver}' pure sandstone mixed with a good deal of sulphate of barytes, and just 

 stained green with carbonate of copper. The wet assay gave readily 1 to 1 J per 

 cent., but the average of the ore treated was 0-92 per cent. I knew, of course, that 

 the ore would be extremely difficult to assay by the dry way — in fact, I could get 

 notliing. We sent two samples to two Cornish assayers, and they could find no- 

 tliing either. Now, here was an extraordinary thing. A copper mine raising 1200 

 Tons a mouth, paying a lordship of nearly £3000 a year, and dividing handsome 

 dividends for eighteen years, all out of nothing. "We cannot push the argument 

 against the dry assay further ; it stands self-convicted. 



7. T('liat ought to he the simple basis of price f 



I am quite aware I approach the most difficult part of my subject, but I believe 

 there is a clear way out of the difficulty. I have, I think, proved that— so 

 far at least as poor ores are concerned — the dry assay is utterly worthless. Of 

 course I assume that no one of any intelhgence will be found to maintain that 



