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Seite 300 - ... the one usually employed by chemical philosophers for the analysis of stones. 8. If any saline matter, or soluble vegetable or animal matter, is suspected in the soil, it will be found in the water of lixiviation used for separating the sand. This water must be evaporated to dryness in a proper dish, at a heat below its boiling point If the solid matter obtained is of a brown colour and inflammable, it may be considered as partly vegetable extract If its smell, when exposed to heat, be like that...
Seite 292 - ... earthy, animal, or vegetable matter, will remain in a state of mechanical suspension for a much longer time ; so that by pouring the water from the bottom of the vessel, after one, two, or three minutes, the sand will be principally separated from the other substances, which, with the water containing them, must be poured into a filter, and after the water has passed through, collected, dried, and weighed.
Seite 299 - ... the weights of the oxides ascertained after they have been heated to redness will denote their quantities. Should any magnesia and lime have escaped solution in the muriatic acid, they will be found in the sulphuric acid ; this, however, is rarely the case ; but the process for detecting them, and ascertaining their quantities, is the same in both instances. The method of analysis by sulphuric acid, is sufficiently precise for all usual experiments ; but if very great accuracy be an object, dry...
Seite 290 - The weights of the vegetable fibres or wood, and of the gravel and stones, should be separately noted down, and the nature of the last ascertained ; if calcareous, they will effervesce with acids ; if siliceous, they will be sufficiently hard to scratch glass ; and if of the common aluminous class of stones, they will be soft, easily cut with a knife, and incapable of effervescing with acids.
Seite 290 - ... the bottom of the dish ; as long as the colour of the wood remains unaltered the heat is not too high, but when the wood begins to be charred the process must be stopped. A small quantity of water will perhaps remain in the soil, even after this operation, but it always...
Seite 291 - ... 3. The greater number of soils, besides gravel and stones, contain larger or smaller proportions of sand of different degrees of fineness ; and it is a necessary operation, the next in the process of analysis, to detach them from the parts in a state of more minute division, such as clay, loam, marie, vegetable and animal matter, and the matter soluble in water.
Seite 308 - Vegetable or animal matters, when finely divided, not only give coherence, but likewise softness and penetrability; but neither they nor any other part of the soil must be in too great proportion ; and a soil is unproductive if it consist entirely of impalpable matter.
Seite 309 - Fahrenheit. Plants and trees, the roots of which are fibrous and hard, and capable of penetrating deep into the earth, will vegetate to advantage in almost all common soils that are moderately dry, and do not contain a very great excess of vegetable matter.
Seite 290 - ... 2. None of the loose stones, gravel, or large vegetable fibres should be divided from the pure soil till after the water is drawn off: for these bodies are themselves often highly absorbent and retentive, and, in consequence, influence the fertility of the land. The next process, however, after that of heating, should be their separation, which may be easily accomplished by the sieve, after the soil has been gently bruised in a mortar. The weights...
Seite 234 - Add to the water thus concentrated a saturated solution of muriate of barytes, as long as any precipitation is produced, taking care to avoid adding an excess. By a previous experiment, let it be ascertained whether this precipitate effervesces or not with diluted muriatic acid, and whether it is entirely dissolved. If it is, the precipitate is of course carbonate of...

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