Bulletin - United States Geological Survey, Numéros 47 à 54

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Page 19 - ... the tube by its own condensations. The retort, somewhat like the well-known drying tube of Liebig in general shape, is easily made of a pipette by bending the tube at one end to a right angle, at the other to a goose-neck, as shown. To the former end is fitted, by a rubber stopper or section of tubing, a glass funnel-tube provided with a stop-cock; the end of the goose-neck passes tightly through a rubber stopper in the upper end of the condensing tube. This is essentially the apparatus, but...
Page 28 - The filtrate from the ferrous sulphide was acidified strongly with sulphuric acid, heated to the boiling point, and treated with potassium permanganate until its characteristic color appeared. The final products of the action of the permanganate upon the tartaric acid are carbonic acid and water, but formic acid appears as an intermediary step in the oxidation. During the first action of the permanganate its conversion to manganous sulphate is rapid, but with the development of formic acid there...
Page 19 - ... goose-neck should be wide enough to prevent the formation of bubbles in it; 0.7 cm. is a good measure for the interior diameter. It is of advantage to heat the bath to a point considerably above the temperature at which the liquid which is to be distilled boils, — something between 130° C. and 140° C. does very well for water...
Page 36 - Flax is, for the first period, 368,371 cwt; — for the second, 830,421 'cwt. I have not been able to obtain any satisfactory information as to the quantity of Linen Cloth exported, but there can be no doubt of a greatly increased consumption at home. Hides, in the first period, imported...
Page 31 - Russell, referring to the incrustation of the grains in certain ferruginous deposits, remarks that if the debris had been deposited in the ocean and exposed to the action of waves and currents, the sands would have been more thoroughly assorted than we now find them, and also that the attrition produced by the waves under such circumstances would have scoured off the incrustation of ferric oxide.3 Button, too, emphasizes the more thoroughly assorted condition of marine sediments as opposed to fluviatile...
Page 5 - The soil of the red lands is derived from the decomposed hornblendic gneisses and slates, which in many places, where exposed in washes or gullies, are seen to be mere stratified clays, containing fragments, more or less angular, of the quartz veins or seams, which are nearly always interbedded with the other rocks of this region. The top stratum of this soil, from two to three inches in depth, has often a dark chocolate-brown color, but below it becomes a bright red, and at varying depths, from...
Page 31 - Ctrsium, rubidium, and thallium. — The filtrate from lithium phosphate was freed from ammonia by boiling ; the phosphoric acid was precipitated by ferric chloride and ammonia, with the usual precautions to secure a suitable proportion of the iron salt and to keep the excess of ammonia at the lowest possible limit, and removed by filtration ; the filtrate from ferric phosphate and ferric hydrate was evaporated to dryness and gently ignited to remove ammonium salts ; the residue thus left was dissolved...
Page 21 - In the filtrate ammonia, in the slightest excess, precipitated ferric and aluminic hydrates from the boiling solution, and these were collected, ignited, and weighed as oxides in the usual manner. The lime was thrown out of the hot ammoniacal filtrate by ammonium oxalate, and the calcium oxalate filtered off after standing twelve hours in the cold. When the amount precipitated exceeded a few milligrams it was dissolved in hydrochloric acid, reprecipitated by ammonia and ammonium oxalate and collected...
Page 20 - ... of water were introduced and evaporated between the second and third, and again between the fourth and fifth distillations. When acetic acid was made use of to free the boric acid, the six distillations with methyl alcohol were made as before ; but, sodium acetate being soluble in methyl alcohol, the intermediate treatments with water were unnecessary. With the fourth portion of methyl alcohol a few drops of acetic acid...
Page 19 - ... of liquid comfortably. The tube of the goose-neck should be wide enough to prevent the formation of bubbles in it ; 0.7 cm. is a good measure for the interior diameter. It is of advantage to heat the bath to a point considerably above the temperature at which the liquid to be distilled boils — something between 130° C. and 140° C. does very well for water, and is not too high for methyl alcohol — and under such circumstances, and.

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