Busby's Hydraulic Orrery. 25 six inches deep, the one following the other, and more effectually than by men at one spit of nine or ten inches deep. The wages paid these girls were 10d. per day. The cost, however, by the girls was per acre £2. 4s. 4d. that is 11s. 4d. per acre more than by men; but Mr. F. is satisfied that the superiority of the girls' work was worth the difference. The girls being unpractised in the use of the spade, was most probably the chief cause of the difference in the price. The spades they used were made for the purpose, being 93 inches long, 8 inches wide, and weighing, with the handle, about 4 lbs. Mr. F. states that 4 acres of land, such as that on which his experiments were made, are necessary to support a horse; which quantity, under the husbandry of the plough, will support nine persons, on the supposition of a common proportion of men, women, and children, by the spade cultivation, the same land will produce subsistence for more than twelve persons. These are im portant facts. I am, Sir, yours, &c. CATO. Nobel Inventions. Hydraulic Orrery. MR. Busby has devised a new and ingenious method of exhibiting the Solar system in motion upon a reservoir of water. The motive impulse is given to the different planets and their satellites by the re-action of several jets of water, issuing from syphons, by which means a silent and apparently spontaneous movement is produced, which exhibits the phenomena of the revolving orbs in a very simple and pleasing manner. It is proposed by the inventor to construct his HYDRAU LIC ORRERY as a scientific ornament upon any pool of still water, in a park or pleasure ground. Models of the contrivance are now publicly exhibiting in the Strand, London, and the Society of Arts have adjudged Mr. Busby their gold Vulcan Medal for the invention. Method of Analysing Vegetable Bodies. By A. B. GRANVILLE, M. D.* THE first steps to be taken consist in examining the vegetable body physically; and next as to its chemical properties. The colour, taste, flavour, smell, external appearance, botanical and physiological characters, state of aggregation, density, &c. belong to the former inquiry; while the experiments made with various tests on the infusion, decoction, extract, tincture of the bark, root, &c. under examination, belong to the latter. In describing the substance and giving an account of the chemical experiments made with it, the same method should be adopted which has been followed during its analysis; and that method may be thus enunciated in the shape of general and aphoristic formulæ. PHYSICAL CHARACTERS. 1. Colour of the bark, root, &c. 2 Nature of its epidermis. 3. Thickness of the bark and the epidermis, individually. 4. Mode in which they adhere together. 5. Whether any of the woody fibres adhere to the epidermis. 6. Smell, flavour, perfume, taste, permanent or evanescent. * From the London Medical Journal for June, 1822. Method of Analysing Vegetable Bodies. 27 7. Has the epidermis the same character with the liber? 8. Is the bark easily powdered? 9. Does it readily attract moisture when exposed to the air? 10. Specific gravity of the bark. 11. Specific gravity when powdered. CHEMICAL CHARACTERS. a, Infusion. 1. A given quantity of the bark, coarsely powdered, infused in a sufficient quantity of cold water for a given number of hours. 2. Filter. Weigh the filtered infusion and the dry residuum on the filter. Examine the smell, taste, colour, and flavour of the infusion. 3. The filtred infusion should now be tried by a. Isinglass. b. Tartarized Antimony. c. Prussiate of Potash. d. Nitrate of Barytes. e. Oxalic Acid. f. Sulphate of Iron. h. Sulphate of Copper. i. Oxalate of Ammonia. m. Tincture of Gall. n. Turmeric Paper. g. Supersulphate of Alumine. o. Litmus Paper. 4. Mark in writing the result of each experiment, and of every precipitate that follows: dry the latter, weigh them, and keep them for further examination. b. Decoction. 1. A given weight of the bark or root, coarsely powdered, boiled in a sufficient quantity of distilled water to the reduction of one-third. 2. Filter the decoction, mark its colour, taste, flavour, and perfume. 3. Test it with the same re-agents, and note the results; and whether or not they be similar to those obtained in treating the infusion. c. Extract. 1. The same quantity of bark, root, or plant, coarsely powdered, is to be subjected to the action of boiling water several successive times. The different decoctions added together are to be slowly evaporated in large vessels, to the consistence of extract. The extract to be weighed, the colour, taste, &c. noted. 2. Ascertain how much of the extract is dissolved in alcohol. Mark the taste, colour, and smell of the resulting tincture. 3. Test the tincture by a. Distilled water. b. Emetine, gelatine, litmus, and turmeric paper, oxalic acid, carbonate of potash; and write down the result. c. Sulphate of iron. d. Nitrate of barytes. g. Prussiate of potash. 5. If any residuum be left after treating the extract with alcohol, subject it to the action of distilled water, exposing it to a gentle heat at the same time, and trying the solution, if any with the above tests. d. Alcoholic Infusion. 1. A given weight of the bark, root, &c. coarsely powdered, is to be infused into a known quantity of alcohol for a given number of days. 2. The smell, colour, taste, perfume, &c. of the resulting infusion are to be noted. 3 The infusion to be tested with a. Distilled water. Description of Newman's Blow-pipe. b. Gallic Acid. c. Sulphate of Iron. 29 4. The residuum, after filtering the alcoholic infusion, is to be weighed and examined. e. Distilled Tincture. 1. The alcoholic solution should be next distilled in a glass retort. 2. Observe whatever phenomena may occur during the distillation. 3. The result of the distillation should be tested with a. Distilled water. b. Prussiate of potash. c. Sulphate of iron.. 4. Dry the residuum; weigh it, note its colour and consistency, and whether it attracts moisture. 5. Is it soluble in water? 6. Is it soluble in alcohol, æther, oil of turpentine, caustic, alkaline solution? 7 In either case, try the solution with the usual reagents. Description of Brooke's or Newman's Blow-pipe. By Mr. CHILDREN.* BROOKE'S, or Newman's Blow-pipe, although not calculated for mineralogical experiments, in others is highly useful. Indeed, when used with atmospheric air, it may be applied to all mineralogical purposes, though still with less advantage than the common blow-pipe in skilfal bands. But when filled with a condensed mixture of oxygen and hodrogen gases in the proportion requisite to * From Berzelius on the Blow-pipe, translated from the French, by J. G. Children. |