As Dalton said, "The doctrine of definite proportions appears mysterious unless we adopt the atomic hypothesis."
Their hypothesis explains so many facts.
The atomic theory has been of priceless value to chemists, but it has more than once happened in the history of science that a hypothesis, after having been useful in the discovery Present and the co-ordination of knowledge, has been aban- position doned and replaced by one more in harmony with later of the discoveries.
at Liege (September 1633), with the words " although he professes that the [Copernican] theory was only adopted by him as a hypothesis."
One hypothesis supplants the various principles of life; the rule of absolute mechanism is as complete in the animal as in the cosmos.
Finally, there is the hypothesis that marsupials are the descendants of placentals, in which case, as was suggested by its discoverer, the placenta of the bandicoots would be a true vestigial structure.
Modern naturalists consider that many of the problems of Australia's remarkable fauna and flora can be best explained by the following hypothesis: - The region now covered by the antarctic ice-cap was in early Tertiary times favoured by a mild climate; here lay an antarctic continent or archipelago.
No speculation of hypothesis has been propounded to account satisfactorily for the origin of the Australian flora.
As a step towards such hypothesis it has been noted that the Antarctic, the South African, and the Australian floras have many types in common.
On the latter hypothesis it has been generally assumed that the wild camels are the descendants of droves of the domesticated breed which escaped when certain central Asian cities were overwhelmed by sand-storms. This theory, according to Professor Leche, is rendered improbable by Dr Sven Hedin's observations on the habits and mode of life of the wild camel.
Apart from the weighty arguments which the development furnishes against the theories of Allman and Mechnikov, it may be pointed out that neither hypothesis gives a satisfactory explanation of a structure universally present in medusae of whatever class, namely the endoderm-lamella, discovered by the brothers O.
It would be necessary to regard this structure as a secondary extension of the endoderm in the tentacle-web, on Allman's theory, or between the outgrowths of the hydrorhiza, on Mechnikov's hypothesis.
These theories, however, contain little that bears directly on the hypothesis of a natural evolution of things.
He is indeed careful to keep right with the orthodox doctrine of creation by saying that he does not believe the world actually arose in this mechanical way out of the three kinds of elements which he here supposes, but that he simply puts out his hypothesis as a mode of conceiving how it might have arisen.
d'etre on any other hypothesis.
For it is almost impossible to prove that any structure, however rudimentary, is useless - that is to say, that it plays no part whatever in the economy; and, if it is in the slightest degree useful, there is no reason why, on the hypothesis of direct creation, it should not have been created.
The careful and complete collection, by Franke, of the philological evidence at present available, has raised this hypothesis into a practical certainty.
The original hypothesis of Baeyer suggested that the course of events is the following: the carbon dioxide is decomposed into carbon monoxide and oxygen, while water is simultaneously split up into hydrogen and oxygen; the hydrogen and the carbon monoxide unite to form formaldehyde and the oxygen is exhaled.
Baeyers hypothesis was entertained by botanists partly because it explained the gaseous interchanges accompanying photosynthesis.
It may be replied that there are such facts, and though they are but few as yet, they suffice to suggest an hypothesis that may eventually prove to be a law.
At any rate this hypothesis suggests an explanation of many hitherto inexplicable facts.
The special Darwinian hypothesis - natural " selection " - may or may not be true; it was at least a fruitful suggestion.
obtained from various persons automatic script affording important new material for investigation and which prima facie supports the spiritualistic hypothesis.
Whether or not further study of the scripts of these writers confirms this hypothesis, it cannot fail to throw light on the nature of the intelligence involved.
The Chemistry of the Sun (1887) is an elaborate treatise on solar spectroscopy based on the hypothesis of elemental dissociation through the intensity of solar heat.
His argument for the Being of God is based on the hypothesis that thought - not individual but universal - is the reality of all things, the existence of this Infinite Thought being demonstrated by the limitations of finite thought.
His silent votes were all given on that hypothesis.
A somewhat similar hypothesis was put forward by R.
Newcomb: "At the present time we can only say that the nebular hypothesis is indicated by the general tendencies of the laws of nature, that it has not been proved to be inconsistent with any fact, that it is almost a necessary consequence of the only theory by which we can account for the origin and conservation of the sun's heat, but that it rests on the assumption that this conservation is to be explained by the laws of nature as we now see them in operation.
Scholars are now almost unanimously agreed that the internal features are best explained by the Graf-Wellhausen hypothesis.
The Graf-Wellhausen hypothesis, that the hierarchical law in its complete form in the Pentateuch stands at the close and not at the beginning of biblical history, that this mature Judaism was the fruit of the 5th century B.C. and not a divinely appointed institution at the exodus (nearly ten centuries previously), has won the recognition of almost all Old Testament scholars.
The Graf-Wellhausen hypothesis (§ 4) does not pretend to be complete in all its details and it is independent of its application to the historical criticism of the Old Testament.
No alternative hypothesis prevails, mere desultory criticism of the internal intricacies being quite inadequate.
But what was matter of immanent assumption with Erigena is in them an equating of two things which have been dealt with on the hypothesis that they are separate, and which, therefore, still retain that external relation to one another.
The depression westward of the Caspian and Aral basins, and the original connexion of these seas, have also come under the close investigation of Russian scientists, with the result that the theory of an ancient connexion between the Oxus and the Caspian has been displaced by the more recent hypothesis of an extension of the Caspian Sea eastwards into Trans-Caspian territory within the postPleiocene age.
above the present level of the Caspian, gives support to this hypothesis, which is further advanced by the ascertained nature of the Kara-kum sands, which appear to be a purely marine formation exhibiting no traces of fluviatile deposits which might be considered as delta deposits of the Oxus.
One hypothesis supposes that the shores of the Mediterranean were originally inhabited by a homogeneous race neither Aryan nor Semitic.
This doctrine or hypothesis he usually speaks of as "the ideal system" or "the theory of ideas"; and to it he opposes his own analysis of the act of perception.
Chronology is against this hypothesis, since Louis and she lived on good terms together for two years after the Crusade.
Every hypothesis must be tested by an appeal to the facts of life, and modified or abandoned if it will not bear examination, unless we are convinced on genuine evidence that it may for a time be employed as a useful approximation, without prejudice to the later stages of the investigation we are conducting.
When the aim of the man of affairs and the hypothesis of the economist was unrestricted competition, and measures were being adopted to realize it, general theory such as the classical economists provided was perhaps a sufficiently trustworthy guide for practical statesmen and men of business.
These facts afford strong support to the hypothesis that the weight of the shell is the original cause of the torsion of the dorsal visceral mass in Gastropods.
But this hypothesis leaves the elevation of the visceral mass and the exogastric coiling of the shell in the ancestral form unexplained.
The actual sinfulness of all men Origen was able to explain by the theological hypothesis of pre-existence and the premundane fall of each individual soul.
The first hypothesis is not negatived by direct evidence, for we do not actually know the ontogeny of any of the Palaeozoic insects; it is, however, rendered highly improbable by the modern views as to the nature and origin of wings in insects, and by the fact that the Endopterygota include none of the lower existing forms of insects.
The hypothesis of "two voices" is now generally abandoned; there is no indication of a debate, of affirmations and responses.
In all the cases which have yet arisen in astronomy the extraneous forces are so small compared with the gravitation of the central body that the orbit is approximately an ellipse, and the preliminary computations, as well as all determinations in which a high degree of precision is not necessary, are made on the hypothesis of elliptic orbits.
Turning to the study of radioactivity, he noticed its association with the minerals which yield helium, and in support of the hypothesis that that gas is a disintegration-product of radium he proved in 1903 that it is continuously formed by the latter substance in quantities sufficiently great to be directly recognizable in the spectroscope.
Berzelius objected to the hypothesis that if two elements form only one compound, then the atoms combine one and one; and although he agreed theory.
A second inconsistency was presented when he was compelled by the researches of Dumas to admit Avogadro's hypothesis; but here he would only accept it for the elementary gases, and denied it for other substances.
Lavoisier, to whom chemistry was primarily the chemistry of oxygen compounds, having developed the radical theory initiated by Guyton de Morveau, formulated the hypothesis that vegetable and animal substances were oxides of radicals composed of carbon and hydrogen; moreover, since simple radicals (the elements) can form more than one oxide, he attributed the same character to his hydrocarbon radicals: he considered, for instance, sugar to be a neutral oxide and oxalic acid a higher oxide of a certain radical, for, when oxidized by nitric acid, sugar yields oxalic acid.
B aeyer has suggested that his hypothesis may also be applied to explain the instability of acetylene and its derivatives, and the still greater instability of the polyacetylene compounds.
Therefore, according to Kekule, the double linkages are in a state of continual oscillation, and if his dynamical notion of valency, or a similar hypothesis, be correct, then the difference between the 1.2 and 1.6 di-derivatives rests on the insufficiency of his formula, which represents the configuration during one set of oscillations only.
It remains, therefore, to consider Erlenmeyer's formula and those derived from the centric hypothesis.
On the centric hypothesis two formulae are possible: (1) due to H.E.
The centric hypothesis has been applied to these rings by Bamberger and others; but as in the previous rings considered, the ordinary (3) (4) (5) representation with double and single linkages generally represents the syntheses, decompositions, &c.; exceptions, however, are known where it is necessary to assume an oscillation of the double linkage.
It remains for excavation to show whether this hypothesis is or is not correct.
He moreover accuses Eratosthenes, (whose determination of a degree he accepts without hesitation) with trusting too much to hypothesis in compiling his map instead of having recourse to latitudes and longitudes deduced by astronomical observations.
It encountered many difficulties, and until the definite proof of the stegomyia hypothesis of yellowfever inoculation made by the United States army surgeons in Cuba in 1900, the greatest problem seemed insoluble.
Beckmann, Ber., 1886, 1 9, p. 9 8 9; 188 7, 20, p. 2580), yielding as final products an acid-amide or anilide, thus: RC(:N OH)R'-RC(OH) :NR' ---> As regards the constitution of the oximes, two possibilities exist, namely >C: NOH, or > C' ?, and the first of these is presumably correct, since on alkylation and subsequent hydrolysis an alkyl hydroxylamine of the type NH 2 OR is obtained, and consequently it is to be presumed that in the alkylated oxime, the alkyl group is attached to oxygen, and the oxime itself therefore contains the hydroxyl group. It is to be noted that the oximes of aromatic aldehydes and of unsymmetrical aromatic ketones frequently exist in isomeric forms. This isomerism is explained by the HantzschWerner hypothesis (Ber., 1890, 23, p. II) in which the assumption is made that the three valencies of the nitrogen atom do not lie in the same plane.
By taking fixed conditions for the hypothesis of such a proposition a definite department of mathematics is marked out.
In calculations the latter hypothesis is made because of its mathematical simplicity.
Poincare, La Science et l'hypothese (Paris, 1st ed., 1902), English translation under the title, Science and Hypothesis (London, 1905); L.
In these he seems suddenly to have cut adrift from every principle the truth of which he had himself so brilliantly demonstrated, and we find him discussing plans based on hypothesis, not knowledge, and on the importance of geographical points without reference to the enemy's field army.
This is a highly ingenious hypothesis to explain the discrepancies of the text, but is, after all, nothing but hypothesis.
Cardan in the 16th century, but this is a mere hypothesis without solid foundation.
The correctness of this hypothesis may, however, be doubted.
To explain these facts, Theodor Grotthus (1785-1822) in 1806 put forward an hypothesis which supposed that the opposite chemical constituents of an electrolyte interchanged partners all along the line between the electrodes when a current passed.
An alternative hypothesis is given by the idea of complex ions.
Hesse's canonical form shows at once that there cannot be more than two independent invariants; for if there were three we could, by elimination of the modulus of transformation, obtain two functions of the coefficients equal to functions of m, and thus, by elimination of m, obtain a relation between the coefficients, showing them not to be independent, which is contrary to the hypothesis.
Admitting Kant's hypothesis that by inner sense we are conscious of mental states only, he holds that this consciousness constitutes a knowledge of the "thing-in-itself" - which Kant denies.
Although Robert Hooke in 1668 and Ignace Pardies in 1672 had adopted a vibratory hypothesis of light, the conception was a mere floating possibility until Huygens provided it with a sure foundation.
The best hypothesis in the writer's opinion is that maintained by Charles Tissot, who sees in the word " Africa " the name of the great Berber tribe, the Aourigha (whose name would have been pronounced Afarika), the modern Aouraghen, now driven back into the Sahara, but in ancient times the principal indigenous element of the African empire of Carthage (Tissot, Geogr.
Supposing Ewing's hypothesis to be correct, it is clear that if the magnetization of a piece of iron were reversed by a strong rotating field instead of by a field alternating through zero, the loss of energy by hysteresis should be little or nothing, for the molecules would rotate with the field and no unstable movements would be possible.'
Ferromagnetism was explained by Ampere on the hypothesis that the magnetization of the molecule is due to an electric current constantly circulating within it.
The theory now most in favour is merely a development of Ampere's hypothesis, and applies not only to ferromagnetics, but to paramagnetics as well.
Thomson (afterwards Lord Kelvin) in 1849 that while no physical evidence could be adduced in support of the hypothesis, certain discoveries, especially in electromagnetism, rendered it extremely improbable (Reprint, p. 344).
Ampere's experimental and theoretical investigation of the mutual action of electric currents, and of the equivalence of a closed circuit to a polar magnet, the latter suggesting his celebrated hypothesis that molecular currents were the cause of magnetism.
N.S.), and in a series of subsequent memoirs, in which the structure of the entosternum, of the coxal glands, of the eyes, of the veno-pericardiac muscles, of the respiratory lamellae, and of other parts, was for the first time described, and in which the new facts discovered were shown uniformly to support the hypothesis that Limulus is an Arachnid.
The balance of various considerations is against the latter hypothesis.
The discovery of the Coptic translation of these Acts in 1897, and its publication by C. Schmidt (Acta Pauli aus der Heidelberger koptischen Papyrushandschrift herausgegeben, Leipzig, 1894), have confirmed what had been previously only a hypothesis that the Acts of Thecla had formed a part of the larger Acts of Paul.
2 The hypothesis of an Arabian Javan, applied to Joel iii.
The famous "nebular hypothesis" of Laplace made its appearance in the Systeme du monde.
Laplace was, moreover, the first to offer a complete analysis of capillary action based upon a definite hypothesis - that of forces "sensible only at insensible distances"; and he made strenuous but unsuccessful efforts to explain the phenomena of light on an identical principle.
But, by hypothesis, n 1P1 is divisible by p!.
Lamarck had put forward the hypothesis that structural alterations acquired by (that is to say, superimposed upon) a parent in the course of its life are transmitted to the offspring, and that, as these structural alterations are acquired by an animal or plant in consequence of the direct action of the environment, the offspring inheriting them would as a consequence not unfrequently start with a greater fitness for those conditions than its parents started with.
Darwin himself, influenced by the consideration of certain classes of facts which seem to favour the Iamarckian hypothesis, was of the opinion that acquired characters are in some cases transmitted.
It is held 1 that the Darwinian doctrine of selection of fortuitous congenital variations is sufficient to account for all cases, that the Lamarckian hypothesis of transmission cf acquired characters is not supported by experimental evidence, and that the latter should therefore be dismissed.
See also for ethnological questions, Mongolian hypothesis: K.
Iranian hypothesis: K.
Stas, the purpose of testing Prout's hypothesis, but he remained more disposed than the Belgian chemist to consider the possibility that it may have some degree of validity.
On this hypothesis we are able to explain the presence of certain poetical pieces both in the book of Chronicles and in the Psalter.
A third hypothesis is that advanced by Karl Rieder (Der Gottesfreund von Oberland, Innsbruck, 1905), who thinks that not even Merswin himself wrote any of the literature, but that his secretary and associate Nicholas of Lowen, head of the House of St John at Griinenworth, the retreat founded by Merswin for the circle, worked over all the writings which emanated from different members of the group but bore no author's names, and to glorify the founder of the house attached Merswin's name to some of them and out of his imagination created "the Friend of God from the Oberland," whom he named as the writer of the others.
Until, however, further evidence is forthcoming in support of this syncytial theory of structure, it would be unwise to regard it as established sufficiently to constitute a serviceable working hypothesis; hence, for the time being, we must accept the assertion that the cell represents the ultimate tissue-unit.
According to the hypothesis of Waldeyer and Thiersch there is perfect equilibrium between the normal epithelium and its supporting structure, the connective tissue, but with advancing age this balance is upset owing to the connective tissue gradually losing its restraining power.
Cohnheim's hypothesis of " embryonic residues " provides that early in the development of the embryo some of the cells, or groups of cells, are separated from their organic continuity during the various foldings that take place in the actively growing embryo.
The " tissue-tension " hypothesis of Ribbert is a combination of the two foregoing.
Hansemann's "anaplasia " hypothesis seeks to find an explanation of the formation of new growths in the absence of the histological differentiation of the cell associated with a corresponding increase in its proliferative power and a suspension, or loss, of its functional activity.
Then we have Beard's " germ-cell " hypothesis, in which he holds that many of the germ-cells in the growing embryo fail to reach their proper position - the generative areas - and settle down and become quiescent in some somatic tissue of the embryo.
The parasitic hypothesis postulates the invasion of a parasite from without, thus making a new growth an infective process.
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