Actinium

“ The distinctive character of the emanation of actinium, as well as of the other radio-active products to which it gives rise, coupled with the permanence of its activity, renders it very probable that actinium will prove to be a new radio-active element of very great activity. ”

“ We shall see that induced activity on bodies is due to a deposit of non-gaseous matter derived from the transformation of the emanations. Each emanation gives a distinctive active deposit which decays at different rates. The active deposits of radium, thorium and actinium are very complex, and consist of several types of matter. Several hours after removal from the emanation the active deposit from radium decays to half-value—26 minutes, for actinium half-value—34 minutes, for thorium half-value— 10.5 hours ”

“ Whether any other heavy atoms besides those of uranium, thorium and radium are thus slowly disintegrating, we can not say, but probably actinium must be added to the list. If any of the other known heavy elements, like gold, lead, barium, bismuth, mercury, are undergoing such a change, it is too slow to be detected even by the delicate test of radio-activity. But it is interesting to note that the only changes of this kind which have thus far been discovered to be going on among the atoms are in some respects similar to the changes which are going on in the organic world among the molecules. ”

“ As yet, the effects of actinism have been more studied in the inanimate than the organic creation. Still, in the vegetable kingdom, its power is known to be of the utmost importance. A seed exposed to the entire sunbeam will not germinate; but bury it in the earth, at a depth sufficient to exclude the light, yet enough to admit actinism, which, like heat, penetrates the earth to some distance, and soon a chemical change will take place; the starch contained in the seed is converted into gum and water, forming the nutriment of the young plant ”

“ Just as, by an immutable law of chemistry, a given weight of calcium carbide yields a given weight of acetylene, and by no amount of ingenuity can be made to produce either more or less; so, by an equally immutable law of physics, the decomposition of a given weight of calcium carbide by water, or the decomposition of a given weight of water by calcium carbide, yields a perfectly definite quantity of heat--a quantity of heat which cannot be reduced or increased by any artifice whatever. ”

“ As explained in the last chapter, after-generation is the secondary production of acetylene which takes place more or less slowly after the primary reaction is finished, proceeding either between calcium hydroxide, merely damp lime, or damp gas and calcium carbide, with an evolution of more acetylene. As it is possible, and indeed usual, to fit a holder of some capacity even to an automatic generator, the simple fact that more acetylene is liberated after the main reaction is over does not matter, for the gas can be safely stored without waste and entirely without trouble or danger. ”

“ During the operation of an acetylene generator a large amount of heat is produced, the quantity of which is beyond human control. It is desirable, for various reasons, that the temperature shall be kept as low as possible. There are three substances present to which the heat may be compelled to transfer itself until it has opportunity to pass into the surrounding atmosphere: the material of which the apparatus is constructed, the gas which is in process of evolution, and whichever of the two bodies-- calcium carbide or water--is in excess in the generator. ”

“ One peculiar and noteworthy feature of acetylene, often overlooked, is that the apparatus is constructed by men who may have been accustomed to gas-making plant all their lives, and who may understand by mere habit how to superintend a chemical operation; but the same apparatus is used by persons who generally have no special acquaintance with such subjects, and who, very possibly, have not even burnt coal-gas at any period of their lives. ”

“ An apparatus has been constructed in France on the lines of some portable fire-extinguishing appliances in which the pressure set up by the evolution of acetylene in a closed space produces a spray of water charged with lime and gas under the pressure obtaining; the liquid being thrown over growing vines or other plants in order to destroy parasitic and other forms of life. The apparatus consists of a metal cylinder fitted with straps so that it can be carried by man or beast. ”

“ It is perhaps desirable to remark that there is scarcely any feature in the generation of acetylene from calcium carbide and water--certainly no important feature--which introduces into practice principles not already known to chemists and engineers. ”

“ Why do plants become scorched under the unclouded sun?
Because the heat rays are in excess. The clouds shut off the scorching light; but, like the blue glass of the photographer's studio, they transmit actinism.
559. What effect has actinism upon vegetation?
It quickens the germination of seeds; and assists in the formation of the colouring matter of leaves. Seeds and cuttings, which are required to germinate quickly, will do so under the effect of blue glass (which is equivalent to saying, the effect of an increased proportion of actinism) , in half the time they would otherwise require. ”

“ It has been repeatedly observed that an actinia has a stinging, or, as it is called, an urticating power over the tissue of other animals. Now, there are in different parts of the body of an actinia innumerable cells, from which, especially the cells on the tentacles, it can dart an invisible thread. ”

“ One of their most important points is that although Molecules differ very materially from each other, according to their kinds; and while Atoms likewise manifest very plainly their "kind," the Corpuscle seems to possess only one "kind," no matter from what form or "kind" of Substance it is thrown off. Just think what this means. It means that the finest particles of Gold, Silver, Iron, Hydrogen, Oxygen, and all the rest of the Elements, are composed of identically the same material, and exhibit no differences in "kind." ”

“ If, for example, the quantity of water present in a generator is more than chemically sufficient to attack all the carbide added, however largo or small that excess may be, no more, and, theoretically speaking, no less, acetylene can ever be evolved than 26 parts by weight of gas for every 64 parts by weight of calcium carbide consumed. ”

“ If the temperature of an acetylene generator rises to such an extent that part of the gas is polymerised into tar, that tar naturally tends to coat the residual carbide lumps, and, being greasy in character, more or less completely protects the interior from further attack. ”

“ In an automatic apparatus, the fundamental idea is that the generating chamber, or one at least of several generating chambers, shall always contain a considerable quantity of undecomposed carbide, and some receptacle always contain a store of water ready to attack that carbide, so that whenever a demand for gas shall arise everything may be ready to meet it. Inasmuch as acetylene is an inflammable gas, it possesses all the properties characteristic of inflammable gases in general ”

“ Rooms containing acetylene apparatus must be of ample size, used for no other purpose, have water-tight floors, be warmed without fireplaces or chimneys, be lighted from outside through an air-tight window by an independent artificial light, have doors opening outwards, efficient ventilation and a store of sand or like material for fire extinction. Strangers must be warned away. ”

“ Taken in the hand, the sea-anemone imparts a slippery feeling, and it seems to have the consistency of leather. To get at its precise form, look at the cut given of Actinia rosea, a British species. Now, please follow closely our description a little while. As the actinia erects itself, attached to a rock or stone, it looks like one of the purses formerly fashionable, if one such could be made to stand of itself erect, and have the frill around the upper end to project in a circle. ”

“ Experiments clearly prove that this change is to be attributed to actinism, and not to heat. Glass has been interposed of a dark blue color, which is transparent to actinism, though opaque to light and heat, and germination has been thereby quickened. Gardeners have long known this fact practically, and are accustomed to raise their cuttings under blue shades. There is no doubt that actinism exercises a powerful and beneficent influence on plants during their whole existence, but science has yet to demonstrate its nature ”

“ Nevertheless, it should be recollected that when the conventional system is retained--useful illuminating effect being sacrificed to absolute illuminating power--acetylene is made to appear cheaper in comparison with all weaker unit sources of light, and dearer in comparison with all stronger unit sources of light than the accompanying table indicates it to be. ”

“ A very simple experiment will show that a notable quantity of heat is set free when calcium carbide is brought into contact with water, and by arranging the details of the apparatus in a suitable manner, the quantity of heat manifested may be measured with considerable accuracy. ”

“ Actinism, the chemical action of sunlight.
Actinomycosis, a disease of a fungous nature on the mouth and lower jaw of cows.
Actium, a town and promontory at the entrance of the Ambracian Gulf (Arta) , in Greece, where Augustus gained his naval victory over Antony and Cleopatra, Sept. 2, 31 B.C.
Acton, an adventurer of English birth, who became prime minister of Naples, but was driven from the helm of affairs on account of his inveterate antipathy to the French (1737-1808) . ”

“ When brought in contact, the oxygen in the water decomposes the calcium in the carbide, and in this decomposition the hydrogen in the water is liberated and unites with the carbon of the carbide, forming a hydrocarbon gas which is acetylene. It is a pure white light of intense brilliancy and high candlepower. The spectrum analysis of acetylene shows that it is almost identical with sunlight, and in consequence delicate shades of color appear according to their true value as under the light of the sun, consequently it penetrates fog to a greater distance than other lights. ”

“ The automatic system of generating acetylene has undoubtedly one advantage in those climates where frost tends to occur frequently, but only to prevail for a short period. As the apparatus is in operation during the evening hours, the heat evolved will, or can be made to, suffice to protect the apparatus from freezing until the danger has passed; whereas if the gas is generated of a morning in a non-automatic apparatus the temperature of the plant may fall to that of the atmosphere before evening, and some portion may freeze unless special precautions are taken to protect it. ”

“ Masses may change—and do change. Molecules may change—and do change. Disintegration and decomposition affect both, and bring to them the death of form. But their substance endures in the Atom. Atoms may change, and decompose, or undergo whatever change that is their fate, and still the Corpuscles, or what lies beyond the Corpuscles will remain. The Atom was once regarded as Eternal, but now even it seems to be capable of dissolving into some finer division of Substance—and perhaps still finer subdivisions await it. ”

“ If a mixture of acetylene with either of the oxides of carbon is led through a red-hot tube, or if a similar mixture is submitted to the action of electric sparks when confined within a closed vessel at some pressure, a decomposition occurs, the whole of the carbon is liberated in the free state, while the hydrogen and oxygen combine to form water. Analogous reactions take place when either oxide of carbon is led over calcium carbide heated to a temperature of 200° or 250° C., the second product in this case being calcium oxide. ”

“ Inasmuch as acetylene is produced by the mere interaction of calcium carbide and water, that is to say, by simply bringing those two substances in the cold into mutual contact within a suitable closed space, and inasmuch as calcium carbide can always be purchased by the consumer in a condition perfectly fit for immediate decomposition, the preparation of the gas, at least from the theoretical aspect, is characterised by extreme simplicity. ”

“ As glass is a fragile and brittle substance, and as it is not capable of bearing large, rapid, and oft-repeated alterations of temperature in perfect safety, it is not a suitable material for the construction of acetylene apparatus or of portions thereof. Hence it follows that a generator must be built of some non-transparent material which prevents the interior being visible when the apparatus is at work. ”

“ As gaseous acetylene will bear a certain amount of pressure in safety--a pressure falling somewhat short of one effective atmosphere--and as pressure naturally rises in a generating apparatus where calcium carbide reacts with water, it becomes possible to use this pressure as a source of energy for several purposes. The pressure of the gas may, in fact, be employed either to force a stream of liquid through a pipe, or to propel certain mechanism. ”

“ Such endothermic bodies are nearly always found to show Endothermic nature of acetylene.considerable violence in their decomposition, as the heat of formation stored up within them is then liberated as sensible heat, and it is undoubtedly this property of acetylene gas which leads to its easy detonation by either heat or a shock from an explosion of fulminating mercury when in contact with it under pressure. ”