Extraction

“ This extraction of Gold is like the extraction of Salt-peter from Earth, where the Workmen also elixiviate one part of the Earth, by the help of Water, which Earth they then throw away, and in room of that put other Earth into the Vessel, which they also elixiviate or wash, and that so often till they have elixiviated all their Earth impregnated with Salt peter. And by the same reason we elicit our Gold from Sand, as they make their Salt-peter. ”

“ The harnessing of science to this peculiar industry is imperative for more reasons than one. As the process of extraction, say of fats, is pushed to its logical conclusion, the task becomes more and more exacting and expensive, demanding the employment of refined methods. It is far more difficult to draw from the material the last ounce of possibly reclaimable fat than to whip out the first ounce. ”

“ Then, also, day by day we are more surely learning that mining in all its branches is a science, and that the treatment of ores and extraction of the metals is daily becoming more and more the work of the laboratory rather than of the rule-of-thumb procedure of the past. ”

“ There is no rubber in the canals, nor is there any rubber, or rather latex, vessels. It is for this reason that, while it is not possible to extract the rubber by tapping, it is possible, by comminution of tissues, to work together or agglomerate the minute particles of rubber set free by breaking the cells which hold them. It is equally evident that chemical agents may be used for extraction by solution, but this process is of less interest in this connection. We may now pass on to examine the methods of handling the shrub and the process of mechanical extraction. ”

“ Extraction, in chemical technology, is a process for separating one substance from another by taking advantage of the varying solubility of the components in some chosen solvent. The term “lixiviation” is used when water is the solvent. In laboratory practice all the common solvents are employed. With small quantities it may suffice to shake the substance with the solvent, the mixture being heated if necessary, filter and distil or otherwise remove the solvent from the distillate. ”

“ The fundamental features are cooking the refuse under vacuum and the ultimate extraction of the oil by the aid of a suitable solvent such as benzine or other equally volatile spirit, or the benzine extraction system may be used from the very beginning, in a single and complete process. ”

“ Gold is classified further as quartz gold (found in veins, &c.) , and wash gold (found in placers, gravel and cement deposits, &c.) . The methods of extraction are mechanical, chemical or both, according to circumstances. Mechanical methods involve the agency of air or water. Air separation is the rude process of winnowing, occasionally practised in localities where water is wanting. ”

“ Although chemical actions must have been observed by man in the most remote times, and also utilized in such processes as the extraction of metals from their ores and in the arts of tanning and dyeing, there is no evidence to show that, beyond an unordered accumulation of facts, the early developments of these industries were attended by any real knowledge of the nature of the processes involved. ”

“ Still another example is the extraction from the earth's crust of minerals and metals accumulated through ages and used to turn out frivolous gadgets or, more disastrously, the materials and machines of civilized warfare. ”

“ As an operation, extraction of teeth is fortunately becoming more rare, but even now large numbers are needlessly sacrificed, in many cases owing to ignorance on the part of the patient of the value of the teeth, at times to lack of knowledge on the part of both operator and patient of the modern methods of conservative dentistry. ”

“ The rupturing of the cells may be accomplished in a variety of ways, as follows: (1) mechanical disintegration, as by grinding in a mortar with sharp sand; (2) freezing the material, by treatment with liquid air, then grinding; (3) killing the cells by drying, by treatment with alcohol or acetone, then grinding the mass in a paint mill with toluene; (4) killing the cells by chemicals (sulfuric acid, 0.5 to 1.0 per cent, or other suitable agents) followed by extraction with water ”

“ The extraction of the gold from alluvial deposits is based on the principle of levigation; the earth is washed, while constantly agitated, by a stream of water, which carries away the lighter portion of the earth, and leaves the coarser particles of the rock and heavier particles of the gold, together with certain substances which accompany it, in the washing apparatus. ”

“ After the extraction we may consume the flesh that is left by sprinkling it with finely levigated salts, and afterwards gargles of wine or oxycrate may be used until the completion of the cure. And since sometimes supernumerary teeth are formed, those that are fixed in the socket we must scrape down with a graving-tool, but those that are not so fixed we must extract with a tooth-extractor. If any tooth grow to an unnatural size, or is broken, we may scrape away the projecting or redundant part of it with a file. ”

“ In all obscure cases an application should be made to the socket of some local anodyne such as tincture of opium{88} or cocaine, and a mouth wash having similar properties should at the same time be prescribed.
(4) DIFFICULTIES, COMPLICATIONS AND SEQUELÆ ARISING DURING EXTRACTION UNDER ANÆSTHETICS.
(a) Tongue slipping back.—During extraction under anæsthetics the tongue not being under control may slip over the larynx, or may be forcibly pushed back by the fingers of the operator. Symptoms of difficult breathing or even arrest of respiration will follow this accident. ”

“ With this system the stronger leach liquors are being acted upon by fresh material, and the nearly "spent" material is being acted on by the weakest liquors, and finally by water, thus ensuring a complete extraction. ”

“ We now come to a highly important part of our subject, the practical treatment of ores and matrixes for the extraction of the metals contained. The methods employed are multitudinous, but may be divided into four classes, namely, washing, amalgamating with mercury, chlorinating, cyaniding and other leaching processes, and smelting. The first is used in alluvial gold and tin workings and in preparing some silver, copper, and other ores for smelting, and consists merely in separating the heavier metals and minerals from their gangues by their greater specific gravity in water. ”

“ In medico-legal researches there is seldom any considerable quantity of the material to work upon. Hence the greatest care must be taken from the commencement not to waste the substance in useless tests, but to study well at the outset what—by the method of extraction used, the microscopic appearance, the reaction to litmus paper, and the solubility in different menstrua—it is likely to be. ”

“ Besides this, there do oft-times occur moil precious Treasures of no profit to any man, which may be brought to most eminent uses (or benefit) by the Extraction, Precipitation, Cheese-making, and Liquefaction delivered by me. For such Metals as the Spirit of Salt do not tie and make fixt in the extractions, ☽ or ♄ makes them such, with which we have taken or fisht the Sol out of the Aqua-regia or Spirit of Salt ”

“ The scarcity of this metal renders the discovery of its ores in this country an object of some importance, and its wide distribution leads to the belief that it exists in sufficient quantities to warrant investment for its extraction from other ores, at no distant day. ”

“ Adams replied that preparation was not necessary for extraction, that people of the worst habits had been treated in that way with no preparation and complete success; that the fault was not of the operator, but of the operation, which must always be liable to failure. Mr. Adams’ 456own method of removing cataract was not this ill-fated scheme of extraction. The second remark is this. It had become much the custom to use hot water for the eyes when weak or inflamed. ”

“ It is admitted that, in the majority of cases, the possible yields are so small as to render reclamation absolutely impossible by any but the solvent extraction process, which undoubtedly constitutes the highest testimony to the efficiency and value of this wonderful British invention it is possible to advance.
[Pg 80]
CHAPTER VI
SAVING THE SCRAP FROM THE SEA
If the human race be extravagant in one, more than in any other direction, it is undoubtedly in connection with the utilization of the harvests of the sea. It is a failing as strongly asserted by the primitive as by the cultured races. ”

“ When substances other than the analytes are suspected to be present in the blood, record their identities to determine possible interferences [2] .
OTHER METHODS: None are known that can determine these constituents simultaneously. Other methods require extraction or distillation for concentration of trace amounts of these chemicals in blood. ”

“ This incomparable and by me newly found out Instrument, being most profitable and commodious for the easie extractions of Metals, and preparations of the dissolving Menstruums, is made of a peculiar earth, and is almost of the figure or likeness of a Bakers Oven, and is either of a bigger or lesser size, according to the quantity any one has a mind to labour in ”

“ And it is equally clear, in cases of chemical inventions, that when, as in the present case, the manufacture claimed as novel is not a new composition of matter, but an extract obtained by the decomposition or disintegration of material substances, it cannot be of importance from what it has been extracted. ”

“ The ‘method of displacement’ has the advantage of expedition, economy, and yielding products possessing considerable uniformity of strength; but the difficulties attending its application by the inexperienced are serious obstacles to its general adoption in the laboratory. It answers admirably for the preparation of all tinctures that are not of a resinous nature, and for most infusions of a woody and fibrous substances, as roots, woods, barks, leaves, seeds, insects, &c., and particularly when cold or tepid water is taken as the solvent. ”

“ But you comprehend the result—man's complete triumph over disease by this process of dissolution aad rehabilitation. The foundation was my ancestor’s discovery that every substance—iron, gold, or any metal, flesh, bone, gristle, etc.,—may be dissolved by some chemical or combination of chemicals, and his inference was that a universal solvent might by their combination, be discovered. ”

“ Cornish Method.—Tin Ore Assay.—The ore to be smelted or assayed should be concentrated to say not less than 50 per cent. of metallic tin; though to obtain satisfactory results it should be brought nearer 70 per cent., as with ore containing less than 40 to 50 per cent. of metal there will be a considerable loss both in the assaying and in the smelting. If the ore to be operated on does not contain this quantity of metal, then the sample (if coarse) must be reduced to a fine state, the gangue being removed by vanning, and the ore saved for the fire assay. ”

“ In the preparation of essences without distillation, the method by percolation or displacement is preferable to that of simple maceration and expression, when the nature of the ingredients and other circumstances render it applicable, as it is not only more economical, but a more concentrated solution may thereby be obtained. ”

“ The fact that such laws exist and only await discovery may be predicated, as it were, from surface indications, in the form of a great variety of disconnected economic facts, with just as much of certainty as the miner who, picking up here and there in the beds of streams fragments of coal or ore which the elements have scattered, predicates that somewhere there must be a larger vein or deposit from which the fragments have been derived. ”

“ THE separation of a liquid from solids suspended in it, by straining through some material pervious to the one and impenetrable to the other, was a familiar process in the remotest antiquity. Observation of various processes in nature, such as the purification of water by trickling through sandy soil, or perhaps the accidental passage of rain-water through an outstretched cloth, a garment, or a tent-cover, would obviously suggest the simple expedient. History fails to record the period of the invention or the name of the individual who first put it in practice. ”

“ For instance, suppose the inquiry to be, from what beginnings, in what manner, and by what process gold or any metal or stone is generated from the original menstruum, or its elements, up to the perfect mineral: or, in like manner, by what process plants are gener­ated, from the first concretion of juices in the earth, or from seeds, up to the perfect plant, with the whole successive motion, and varied and uninterrupted efforts of nature; and the same inquiry be made as to a regularly deduced system of the generation of animals from coition to birth, and so on of other bodies. ”

“ The assay was for one-half quintal of ore which was obtained from a hole made in these new mines from the crust of the earth to the openings and veins whence the said Ygolote Indians evidently had been and were obtaining it, and when we had dug down about ten estados. The said assay was made by refining, by feeding [the dust of the ore] upon sixteen libras of lead. From it was obtained a grain that resembled silver, which, having been weighed by me, weighed a trifle more than one real. ”

“ We bail it out into them, and after the [Pg 105] water strains out a little, we tie them up and load them on one of these cars and run them out to the 'extractor.'"
"What kind of a thing is an extractor?"
"It is something that shakes the water out. It has a big basket inside that goes around like lightning." ”

“ It has been said that classification is the basis of all science, and it most certainly is the basis of the scientific disposal of refuse. Refuse matter is most varied in its [85] nature, and the items of which it is composed—excrement, rags, bones, paper, straw, sawdust, and other packing materials, cinders and ashes, old crockery, broken glass, old metal, &c.—all demand a different method of treatment. ”