Ovations On Other Sites - Ovation 22 Ovations 06Calibrated Amber chose the topics covered by Ovations On Other Sites - Ovation 22 without reflecting upon the choices others have made. And when you have finished learning all that you can and understand all that you have learned, vacationing with friends in the desert is another way to look at things in a different light. |
OvationsOvation 01Ovation 02 Ovation 03 Ovation 04 Ovation 05 Ovation 06 Ovation 07 Ovation 08 Ovation 09 Ovation 10 Ovation 11 Ovation 12 Ovation 13 Ovation 14 Ovation 15 Ovation 16 Ovation 17 Ovation 18 Ovation 19 Ovation 20 Ovation 21 Ovation 22 Ovation 23 Ovation 24 SitemapsSitemap 1Sitemap 2 Sitemap 3 |
Sulphide of iron formed during an assay will remain diffused through the slag, instead of fusing into a button of regulus, if the slag contain sulphide of sodium. The same is true of other sulphides if not present in too great a quantity, and if the temperature is not too high. _Speises_ are compounds of a metal or metals with arsenic. They are chiefly of interest in the metallurgy of nickel, cobalt, and tin. They are formed by heating the metal or ore in covered crucibles with arsenic and, if necessary, a reducing agent. The product is fused with more arsenic under a slag, consisting mainly of borax. They are very fusible, brittle compounds. On exposure to the air at a red heat the arsenic and the metal simultaneously oxidize. When iron, cobalt, nickel, and copper are present in the same speise, they are eliminated in the order mentioned. _Slags_ from which metals are to be separated should not be too acid; at least, in those cases in which the metal is to be reduced from a compound, as well as separated from earthy impurities. Where the object is simply to get a button of metal from a substance in which it is already in the metallic state, but mixed with dross (made up of metallic oxides, such as those of zinc or iron), from which it is desired to separate it, an acid flux like borax is best; or, if the metal is easily fusible, and there would be danger of loss of metal by oxidation or volatilising, it may be melted under a layer of resin or fat. Common salt is sometimes used with a similar object, and is often useful. Under certain conditions, however, it has a tendency to cause the formation of volatile chlorides with a consequent loss of metal. |
First and foremost for every student of Norman and early Angevin history is the work of Bishop STUBBS. With a more direct, personal interest in the growth of institutions, still in his Constitutional History and in his prefaces to the volumes he edited for the Master of the Rolls he discussed the narrative history of the whole age and very fully the reigns of Henry II and his two sons. The characteristic of Bishop Stubbs's work, which makes it of especial value to the student of the present generation, is the remarkable clearness with which he saw the essential meaning of his material and its bearing on the problem under discussion. While he generally neglected a wide range of material of great value to the historian of institutions--the charters and legal documents--and did not always formulate clearly in his mind the exact problem to be solved, yet the keenness with which he detected in imperfect material the real solution is often marvellous. Again and again the later student finds but little more to do than to prove more fully and from a wider range of material the intuitive conclusions of his master. |
More Ovations From Calibrated Amber | ||
This page is Copyright © Calibrated Amber. All Rights Reserved. Ovations On Other Sites - Ovation 22 is a production of Calibrated Amber and may not be reproduced electronically or graphically for commercial uses. Personal reproductions and browser or search engine caching are acceptable. | ||