A Journal of Natural Philosophy, Chemistry and the Arts, 19-20. kötet

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376. oldal - These trees grow in great abundance all over this part of Bambarra. They are not planted by the natives, but are found growing naturally in the woods; and in clearing woodland for cultivation, every tree is cut down but the shea. The tree itself very much resembles the American oak, and the fruit — from the kernel of which, being first dried in the sun, the butter is prepared by boiling the kernel in water — has somewhat the appearance of a Spanish olive.
38. oldal - Solution of sulphate of potash was placed in contact with the negatively electrified point, pure water was placed in contact with the positively electrified point, and a weak solution of ammonia was made the middle link of the conducting chain ; so that no sulphuric acid could pass to the positive point in the distilled water without passing through the solution of ammonia. The...
319. oldal - Some general observations on the relations of the bases of potash and soda to other bodies Should the bases of potash and soda be called metals'? The greater number of philosophical persons to whom this question has been put, have answered in the affirmative. They agree with metals in opacity, lustre, malleability, conducting powers as to heat and electricity, and in their qualities of chemical combination.
344. oldal - ... is -a small building, similar to a pigeon cote, for the hens to lay in, with frames covered with net to slide before each nest ; the house is dry, light, and well ventilated, kept free from dirt, by having the nests and walls white-washed two or three times a year, and the floor covered once a week with fresh ashes : when I wish to procure chickens, I take the opportunity of setting many hens together, confining each to her respective nest ; a boy attends morning and evening to let any off that...
320. oldal - Potasium and Sodium are the names by which I have ventured to call the two new substances : and whatever changes of theory, with regard to the composition of bodies, may hereafter take place, these terms can scarcely express an error ; for they may be considered as implying simply the metals produced from potash and soda. I have consulted with many of the most eminent scientific persons in this country, upon the methods of derivation, and the one I have adopted has been the one most generally approved....
87. oldal - If the foregoing conjectures be just, distinct regions are allotted to the electrical phenomena of our atmosphere. Here below, we have thunder and lightning, from the unequal distribution of the electric fluid among the clouds; in the loftier regions whither the clouds never reach, we have the various gradations of falling stars ; till, beyond the limits of our crepuscular atmosphere, the fluid is put into motion in sufficient masses to hold a determined course, and exhibit the different appearances...
45. oldal - ... alternations were put together: the positive energy being exhibited on the side of the alkali, and the negative on that of the acid. Arrangements of plates of zinc, pieces of moistened pasteboard, and moistened quicklime, to the number of...
378. oldal - On opening the shell of the seed or nut, which is of a fine chesnut colour, smooth, and brittle ; the kernel appears of the size and shape of a blanched almond : the kernels are bruised, on a smooth stone, to the consistency of cream, or of a fine pulpy matter ; which is then put into a cloth bag, with a moderate weight laid on, and left to stand, till the oil, or fat, is expressed, which becomes immediately of the consistency of hog's-lard, and is of a delicate white colour. Its uses are in medicine...
38. oldal - ... whether they would not likewise pass through chemical menstrua, having stronger attractions for them; and it seemed reasonable to suppose, that the same power which destroyed elective affinity in the vicinity of the metallic points, would likewise destroy it, or suspend its operation, throughout the whole of the circuit.
52. oldal - Allowing combination to depend upon the balance of the natural electrical energies of bodies, it is easy to conceive that a measure may be found of the artificial energies, as to intensity and quantity produced in the common electrical machine, or the Voltaic apparatus, capable of destroying this equilibrium; and such a measure would enable us to make a scale of electrical powers corresponding to degrees of affinity.

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