The term "cobalt" is met with in the writings of Paracelsus, Agricola and Basil Valentine, being used to denote substances which, although resembling metallic ores, gave no metal on smelting.
He held that every fermentation consisted of molecular motion which is transmitted from a substance in a state of chemical motion - that is, of decomposition - to other substances, the elements of which are loosely held together.
Uracil and its homologues may be obtained in many cases from the hydrouracils by the action of bromine, and subsequent elimination of the elements of hydrobromic acid; or by the condensation of aceto-acetic ester and related substances with urea, thiourea, guanidine, &c. Uracil, C4H402N2, crystallizes in colourless needles, is soluble in hot water and melts with decomposition at 335° C. Hydrouracil, C4H602N2, is obtained by the action of bromine and caustic alkalis on succinamide (H.
When he began his active career it was generally believed that, although some instances of the synthetical production of organic substances had been observed, on the whole organic chemistry must remain an analytical science and could not become a constructive one, because the formation of the substances with which it deals required the intervention of vital activity in some shape.
To this attitude he offered uncompromising opposition, and by the synthetical production of numerous hydrocarbons, natural fats, sugars and other bodies he proved that organic compounds can be formed by ordinary methods of chemical manipulation and obey the same laws as inorganic substances, thus exhibiting the "creative character in virtue of which chemistry actually realizes the abstract conceptions of its theories and classifications - a prerogative so far possessed neither by the natural nor by the historical sciences."
The common mushroom (Agaricus campestris) is propagated by spores, the fine black dust seen to be thrown off when a mature specimen is laid on white paper or a white dish; these give rise to what is known as the "spawn" or mycelium, which consists of whitish threads permeating dried dung or similar substances, and which, when planted in a proper medium, runs through the mass, and eventually develops the fructification known as the mushroom.
The word "flocculent" is used of many substances which have a fleecy or "flock"-like appearance, such as a precipitate of ferric hydrate.
Thus the Ionian school of philosophy, which began with Thales, sought for the beginning of all things in various material substances, water, air, fire (see Ionian School).
These substances were regarded as being in some sense alive, and taking some active part in the development of being.
The views of Becher on the composition of substances mark little essential advance on those of the two preceding centuries, and the three elements or principles of salt, mercury and sulphur reappear as the vitrifiable, the mercurial and the combustible earths.
His ideas and experiments on the nature of minerals and other substances are voluminously set forth in his Physica Subterranea (Frankfort, 1669); an edition of this, published at Leipzig in 1703, contains two supplements (Experimentum chymicum novum and Demonstratio Philosophica), proving the truth and possibility of transmuting metals, Experimentum novum ac curiosum de minera arenaria perpetua, the paper on timepieces already mentioned and also Specimen Becherianum, a summary of his doctrines by Stahl, who in the preface acknowledges indebtedness to him in the words Becheriana sunt quae profero.
If the human soul is a force in the narrower sense, a substance, and not a combination of substances, then, as in the nature of things there is no transition from existence to non-existence, we cannot naturally conceive the end of its existence, any more than we can anticipate a gradual annihilation of its existence."
While the majority of the Nematodes are parasites, there are many that are never at any period of their life parasitic. These free-living forms are found everywhere - in salt and fresh water, in damp earth and moss, and among decaying substances; they are always minute in size, and like many other lower forms of life, are capable of retaining their vitality for a long period even when dried, which accounts for their wide distribution; this faculty is also possessed by certain of the parasitic Nematodes, especially by those which lead a free existence during a part of their life-cycle.
The receiver was based on the change of friction produced by the passage of an electric current through the point of contact of certain substances in relative motion.
One may regard him as an idealist, though Scottish intuitionalism - especially in the writings of Professor John Veitch - has claimed him for its own; and indeed Descartes's two substances of active mind and passive extended matter are very much akin to " Natural Dualism."
A difficult question arose for Descartes's philosophy, when it had to explain the union in man of the absolutely opposite substances, 4 Cf.
We must also excuse Hippocrates for his belief that the human body is composed of four basic substances called "humors" that must be kept in balance.
It would know all my food sensitivities and alert me if a single bite had these substances in it.
In the future, we will paint surfaces with substances full of nanites that will absorb sunlight and turn it into electricity, transforming any object we paint into a clean energy creator.
Their usefulness did not depend on making the patient swallow substances for the most part harmful (the harm was scarcely perceptible, as they were given in small doses), but they were useful, necessary, and indispensable because they satisfied a mental need of the invalid and of those who loved her--and that is why there are, and always will be, pseudo-healers, wise women, homeopaths, and allopaths.