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LIFE
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LIFE , the popular name for the activity See also:peculiar to See also:protoplasm (q.v.). This conception has been extended by See also:analogy to phenomena different in See also:kind, such as the activities of masses of See also:water or of See also:air, or of machinery, or by another analogy, to the duration of a composite structure, and by See also:imagination to real or supposed phenomena such as the manifestations of incorporeal entities. From the point of view of exact See also:science life is associated with See also:matter, is displayed only by living bodies, by all living bodies, and is what distinguishes living bodies from bodies that are not alive. See also:Herbert See also:Spencer's See also:formula that life is " the continuous See also:adjustment of See also:internal relations to See also:external relations " was the result of a profound and subtle See also:analysis, but omits the fundamental See also:consideration that we know life only as a quality of and in association with living matter. In developing our conception we must discard from consideration the complexities that arise from the organization of the higher living bodies, the See also:differences between one living See also:animal and another, or between plant and animal. Such differentiations and integrations of living bodies are the subject-matter of discussions on See also:evolution; some will see in the See also:play of circumambient See also:media, natural or supernatural, on the simplest forms of living matter, sufficient explanation of the development of such matter into the highest forms of living organisms; others will regard the potency of such living matter so to develop as a mysterious and peculiar quality that must be added to the conception of life. Choice amongst these alternatives need not complicate investigation of the nature of life. The explanation that serves for the evolution of living matter, the vehicle of life, will serve for the evolution of life. What we have to See also:deal with here is life in its simplest See also:form. The See also:definition of life must really be a description of the essential characters of life, and we must set out with an investigation of the characters of living substance with the See also:special See also:object of detecting the differences between organisms and unorganized matter, and the differences between dead and living organized matter. Living substance (see PROTOPLASM), as it now exists in all animals and See also:plants, is particulate, consisting of elementary organisms living independently, or grouped in communities, the communities forming the bodies of the higher animals and plants. These small particles or larger communities are subject to accidents, internal or external, which destroy them, immediately or slowly, and thus life ceases; or they may See also:wear out, or become clogged by the products of their own activity. There is no See also:reason to regard the mortality of protoplasm and the consequent limited duration of life as more than the necessary consequence of particulate See also:character of living matter (see See also:LONGEVITY). Protoplasm, the living material, contains only a few elements, all of which are extremely See also:common and none of which is peculiar to it. These elements, however, form compounds characteristic of living substance and for the most See also:part peculiar to it. Proteid, which consists of See also:carbon, See also:hydrogen, See also:nitrogen, See also:oxygen and See also:sulphur, is See also:present in all protoplasm, is the most complex of all organic bodies, and, so far, is known only from organic bodies. A multitude of See also:minor and simpler organic compounds, of which carbohydrates and fats are the best known, occur in different protoplasm in varying forms and proportions, and are much less isolated from the inorganic See also:world. They may be stages in the elaboration or disintegration of protoplasm, and although they were at one See also:time believed to occur only as products of Ivingmatter, are gradually being conquered by the synthetic chemist. Finally, protoplasm contains various inorganic substances, such as salts and water, the latter giving it its varying degrees of liquid consistency. We attain, therefore, our first generalized description of life as the See also:property or peculiar quality of a substance composed of none but the more common elements, but of these elements grouped in various ways to form compounds ranging from proteid, the most complex of known substances to the simplest salts. The living substance, moreover, has its mixture of elaborate and See also:simple compounds associated in a See also:fashion that is peculiar. The older writers have spoken of protoplasm or the See also:cell as being in a sense " manufactured articles "; in the more See also:modern view such a conception is replaced by the statement that protoplasm and the cell have behind them a See also:long See also:historical See also:architecture. Both ideas, or both modes of expressing what is fundamentally the same See also:idea, have this in common, that life is not a sum of the qualities of the chemical elements contained in protoplasm, but a See also:function first of the peculiar architecture of the mixture, and then of the high complexity of the compounds contained in the mixture. The qualities of water are no sum of the qualities of oxygen and hydrogen, and still less can we expect to explain the qualities of life without regard to the immense complexity of the living substance. We must now examine in more detail the differences which exist or have been alleged to exist between living organisms and inorganic bodies. There is no essential difference in structure. Confusion has arisen in regard to this point from attempts to compare organized bodies with crystals, the comparison having been. suggested by the view that as crystals present the highest type of inorganic structure, it was reasonable to compare them with organic matter. Differences between crystals and organized bodies have no bearing on the problem of life, for organic substance must be compared with a liquid rather than with a crystal, and differs in structure no more from inorganic liquids than these do amongst themselves, and less than they differ from crystals. Living matter is a mixture of substances chiefly dissolved in water; the comparison with the crystals has led to a supposed distinction in the mode of growth, crystals growing by the superficial apposition of new particles and living substance by intussusception. But inorganic liquids also grow in the latter mode, as when a soluble substance is added to them. The phenomena of See also:movement do not See also:supply any See also:absolute distinction. Although these are the most obvious characters of life, they cannot be detected in quiescent seeds, which we know to be alive, and they are displayed in a fashion very like life by inorganic foams brought in contact with liquids of different See also:composition. Irritability, again, although a notable quality of living substance, is not peculiar to it, for many in-organic substances See also:respond to external stimulation by definite changes. Instability, again, which lies at the See also:root of Spencer's definition " continuous adjustment of internal relations to external relations " is displayed by living matter in very varying degrees from the apparent absolute quiescence of frozen seeds to the activity of the central See also:nervous See also:system, whilst there is a similar range amongst inorganic substances. The phenomena of See also:reproduction present no fundamental distinction. Most living bodies, it is true, are capable of reproduction, but there are many without this capacity, whilst, on the other See also:hand, it would be difficult to draw an effective distinction between that reproduction of simple organisms which consists of a sub-See also:division of their substance with consequent resumption of symmetry by the See also:separate pieces, and the breaking up of a drop of See also:mercury into a number of droplets. Consideration of the mode of origin reveals a more real if not an absolute distinction. All living substance so far as is known at present (see See also:BIOGENESIS) arises only from already existing living substance. It is to be noticed, however, that See also:green plants have the See also:power of See also:building up living substance from inorganic material, and there is a certain analogy between the building up of new living material only in association with pre-existing living material, and the greater readiness with which certain inorganic reactions take See also:place if there already be present some trace of the result of the reaction. The real distinction between living matter and inorganic matter is chemical. Living substance always contains proteid, and although we know that proteid contains only common inorganic elements, we know neither how these are combined to form proteid, nor any way in which proteid can be brought into existence except in the presence of previously existing proteid. The central position of the problem of life lies in the See also:chemistry of proteid, and until that has been fully explored, we are unable to say that there is any problem of life behind the problem of proteid. Comparison of living and lifeless organic matter presents the initial difficulty that we cannot draw an exact See also:line between a living and a dead organism. The higher " warm-blooded " creatures appear to present the simplest See also:case and in their life-See also:history there seems to be a point at which we can say " that which was alive is now dead." We See also:judge from some See also:major See also:arrest of activity, as when the See also:heart ceases to See also:beat. Long after this, however, various tissues remain alive and active, and the event to which we give the name of See also:death is no more than a superficially visible See also:stage in a See also:series of changes. In less highly integrated organisms, such as " See also:cold-blooded " vertebrates, the point of death is less conspicuous, and when we carry our observations further down the See also:scale of animal life, there ceases to be any salient phase in the slow transition from life to death. The distinction between life and death is made more difficult by a consideration of cases of so-called " arrested vitality." If See also:credit can be given to the stories of See also:Indian fakirs, it appears that human beings can pass voluntarily into a See also:state of suspended animation that may last for See also:weeks. The state of involuntary See also:trance, sometimes mistaken for death, is a similar occurrence. A. See also:Leeuwenhoek, in 1719, made the remarkable See also:discovery, since abundantly confirmed, that many animalculae, notably tardigrades and rotifers, may be completely desiccated and remain in that See also:condition for long periods without losing the power of awaking to active life when moistened with water. W. Preyer has more recently investigated the matter and has given it the name " anabiosis." Later observers have found similar occurrences in the cases of small nematodes, rotifers and bacteria. The capacity of plant seeds to remain dry and inactive for very long periods is still better known. It has been supposed that in the case of the plant seeds and still more in that of the animals, the condition of anabiosis was merely one in which the See also:metabolism was too faint to be perceptible by See also:ordinary methods of observation, but the elaborate experiments of W. Kochs would seem to show that a See also:complete arrest of vital activity is compatible with viability. The categories, " alive " and " dead," are not sufficiently distinct for us to add to our conception of life by comparing them. A living organism usually displays active metabolism of proteid, but the metabolism may slow down, actually cease and yet reawaken; a dead organism is one in which the metabolism has ceased and does not reawaken. Origin of Life.—It is See also:plain that we cannot discuss adequately the origin of life or the possibility of the artificial construction of living matter (see See also:ABIOGENESIS and BIOGENESIS) until the chemistry of protoplasm and specially of proteid is more advanced. The investigations of O. Butschli have shown how a See also:model of protoplasm can be manufactured. Very finely triturated soluble particles are rubbed into a smooth See also:paste with an oil of the requisite consistency. A fragment of such a paste brought into a liquid in which the solid particles are soluble, slowly expands into a See also:honeycomb like foam, the walls of the See also:minute vesicles being films of oil, and the contents being the soluble particles dissolved in droplets of the circumambient liquid. Such a model, properly constructed, that is to say, with the vesicles of the foam microscopic in See also:size, is a marvellous See also:imitation of the See also:appearance of protoplasm, being distinguishable from itonly by a greater symmetry. The nicely balanced conditions of See also:solution produce a state of unstable See also:equilibrium, with the result that internal streaming movements and changes of shape and changes of position in the model simulate closely the corresponding manifestations in real protoplasm. The model has no power of recuperation ;in a comparatively See also:short time equilibrium is restored and the resemblance with protoplasm disappears. But it suggests a method by which, when the chemistry of protoplasm and proteid is better known, the proper substances which compose protoplasm may be brought tpgether to form a simple kind of protoplasm. It has been suggested from time to time that conditions very unlike those now existing were necessary for the first appearance of life, and must be repeated if living matter is to be constructed artificially. No support for such a view can be derived from observations of the existing conditions of life. The chemical elements involved are abundant; the See also:physical conditions of temperature pressure and so forth at which living matter is most active, and within the limits of which it is confined, are See also:familiar and almost See also:constant in the world around us. On the other hand, it may be that the initial conditions for the See also:synthesis of proteid are different from those under which proteid and living matter display their activities. E. Pfluger has argued that the analogies between living proteid and the compounds of See also:cyanogen are so numerous that they suggest cyanogen as the starting-point of protoplasm. Cyanogen and its compounds, so far as we know, arise only in a state of incandescent See also:heat. Pfluger suggests that such compounds arose when the See also:surface of the See also:earth was incandescent, and that in the long See also:process of cooling, compounds of Cyanogen and See also:hydrocarbons passed into living protoplasm by such processes of transformation and polymerization as are familiar in the chemical See also:groups in question, and by the acquisition of water and oxygen. His theory is in consonance with the See also:interpretation of the structure of protoplasm as having behind it a long historical architecture and leads to the obvious conclusion that if protoplasm be constructed artificially it will be by a series of stages and that the product will be simpler than any of the existing animals or plants. Until greater knowledge of protoplasm and particularly of proteid has been acquired, there is no scientific See also:room for the See also:suggestion that there is a mysterious See also:factor differentiating living matter from other matter and life from other activities. We have to scale the walls, open the windows, and explore the See also:castle before crying out that it is so marvellous that it must contain ghosts. As may be supposed, theories of the origin of life apart from doctrines of special creation or of a See also:primitive and slow spontaneous See also:generation are See also:mere fantastic speculations. The most striking of these suggests an extra-terrestrial origin. H. E. See also:Richter appears to have been the first to propound the idea that life came to this See also:planet as See also:cosmic dust or in meteorites thrown off from stars and See also:planets. Towards the end of the 19th See also:century See also:Lord See also:Kelvin (then See also:Sir W. See also:Thomson) and H. von See also:Helmholtz independently raised and discussed the possibility of such an origin of terrestrial life, laying stress on the presence of hydrocarbons in meteoric stones and on the indications of their presence revealed by the spectra of the tails of comets. W. Preyer has criticized such views, grouping them under the phrase " theory of cosmozoa," and has suggested that living matter preceded inorganic matter. Preyer's view, however, enlarges the conception of life until it can be applied to the phenomena of incandescent gases and has no relation to ideas of life derived from observation of the living matter we know. LIFE-See also:BOAT, and LIFE-SAVING SERVICE. The See also:article on DROWNING AND LIFE-SAVING (q,v.) deals generally with the means of saving life at See also:sea, but under this heading it is convenient to include the appliances connected specially with the life-boat service. The ordinary open boat is unsuited for life-saving in a stormy sea, and numerous contrivances, in regard to which the See also:lead came from See also:England, have been' made for securing the best type of life-boat. The first life-boat was conceived and designed by Lionel Lukin, a See also:London coachbuilder, in 1785. Encouraged by the See also:prince of See also:Wales (See also:George IV.), Lukin fitted up a See also:Norway See also:yawl as a life-boat, took out a patent for it, and wrote a pamphlet descriptive of his " Insubmergible Boat." Buoyancy he obtained by means of a projecting gunwale of See also:cork and air-See also:chambers inside -one of these being at the See also:bow, another at the stern. Stability he secured by a false See also:iron See also:keel. The self-righting and self-emptying principles he seems not to have thought of; at all events he did not See also:compass them. Despite the patronage of the prince, Lukin went to his See also:grave a neglected and disappointed See also:man. But he was not altogether unsuccessful, for, at the See also:request of the Rev Dr See also:Shairp, Lukin fitted up a See also:coble as an " unimmergible " life-boat, which was launched at Bamborough, saved several lives the first See also:year and afterwards saved many lives and much property. Public apathy in regard to shipwreck was temporally swept
away by the See also:wreck of the " See also:Adventure " of See also:Newcastle in 1789. This See also:vessel was stranded only 300 yds. from the See also:shore, and her See also:crew dropped, one by one, into the raging breakers in presence of thousands of spectators, none of whom dared to put off in an ordinary boat to the See also:rescue. An excited See also:meeting among the See also:people of See also:South See also:Shields followed; a See also:committee was formed, and premiums were offered for the best See also:models of a life-boat. This called forth many plans, of which those of See also: In 1908 the receipts were £115,303,
the See also:expenditure £90,335.
In 1882 the Institution undertook, with the view of diminishing the loss of life among the coast fishermen, to provide the masters and owners of fishing-vessels with trustworthy aneroid barometers, at about a third of the See also:retail See also:price, and in 1883 the See also:privilege was extended to the masters and owners of coasters under too tons See also:burden. At the end of 1901 as many as 4417 of these valuable See also:instruments had been supplied. In 1889 the committee of management secured the passing of the Removal of Wrecks See also:Act 1877 See also:Amendment Act, which provides for the removal of wrecks in non-navigable See also:waters which might prove dangerous to life-boat crews
At the date of the institution's second See also:report it had contributed to the saving of three See also:hundred and See also:forty-two lives, either by its own life-saving apparatus or by other means for which it had granted rewards. With fluctuating success, both as regards means and results, the institution continued its good See also:work—saving many lives, and occasionally losing a few brave men in its tremendous battles with the sea. Since the See also:adoption of the self-righting boats, loss of life in the service has been comparatively small and infrequent.
Towards the See also:middle of the 19th century the life-boat cause appeared to lose See also:interest with the British public, though the life-saving work was prosecuted with unremitting zeal, but the increasing loss of life by shipwreck, and a few unusually severe disasters to life-boats, brought about the reorganization of the society in 185o. The Prince See also:Consort became See also:vice-patron of the institution in See also:conjunction with the See also: In reply to- the offer no fewer than two hundred and eighty models were sent in, not only from all parts of the United Kingdom, but from See also:France, See also:Germany, See also: In its See also:early years the institution placed the See also:mortar apparatus of See also:Captain Manby at many stations, and provided for the wants of sailors and others saved from shipwreck,—a See also:duty subsequently discharged by the " See also:Ship-wrecked Fishermen and Mariners' Royal Benevolent Society."
and others. Under its provisions numerous highly dangerous wrecks have been removed.
In 1893 the chairman of the Institution moved a See also:resolution in the House of Commons that, in order to decrease the serious loss of life from shipwreck on the coast, the British See also:Government should provide either telephonic or telegraphic communication between all the coast-guard stations and See also:signal stations on the coast of the United Kingdom; and that where there are no coast-guard stations the See also:post offices nearest to the life-boat stations should be electrically connected, the object being to give the earliest possible See also:information to the life-boat authorities at all times, by See also:day and See also:night, when the life-boats are required for service; and further, that a Royal See also:Commission should be appointed to consider the desirability of electrically connecting the See also:rock lighthouses, See also:light-See also:ships, &c., with the shore. The resolution was agreed to without a division, and its intention has been practically carried out, the results obtained having proved most valuable in the saving of life.
On the 1st of January 1898 a See also:pension and gratuity See also:scheme was introduced by the committee of management, under which life-boat coxswains, bowmen and signalmen of long and meritorious service, retiring on See also:account of old See also:age, See also:accident, See also:ill-See also:health or abolition of See also:office, receive special allowances as a See also:reward for their good services. While these payments act as an incentive to the men to See also:discharge their duties satisfactorily, they at the same time assist the committee of management in their effort to obtain the best men for the work. For many years the Institution has given See also:compensation to any who may have received injury while employed in the service, besides granting liberal help to the widows and dependent relatives of any in the service who lose their own lives when endeavouring to rescue others.
A very marked advance in improvement in See also:design and suit-ability for service has been made in the life-boat since the re-organization of the Institution in 1883, but principally since
1887, when, as the result of an accident in See also:December 1886 to two self-righting life-boats in See also:Lancashire, twenty-seven out of twenty-nine of the men who manned them were drowned. At this time a permanent technical sub-committee was appointed by the Institution, whose object was, with the assistance of an eminent consulting See also:naval architect—a new post created—and the Institution's See also:official experts, to give its careful See also:attention to the designing of improvements in the life-boat and its equipment, and to the scientific consideration of any inventions or proposals submitted by the public, with a view to adopting them if of See also:practical utility. Whereas in 1881 the self-righting life-boat of that time was looked upon as the Institution's special life-boat, and there were very few life-boats in the Institution's fleet not of that type, at the close of 1901 the life-boats of the Institution included 6o non-self-righting boats of various types, known by the following designations: See also:Steam life-boats 4, See also:Cromer 3, See also:Lamb and See also: The Institution's present policy is to allow the men who man the life-boats, after having seen and tried by deputation. the various types, to select that in which they have the most See also:con= fidence. The present life-boat of the self-righting type (fig. 2) differs materially from its predecessor, the stability being increased and the righting power greatly improved. The test of efficiency in this last quality was formerly considered sufficient if the boat would quickly right herself in smooth water without her crew and See also:gear, but every self-righting life-boat now built bythe Institution will right with her full crew and gear on board, with her sails set and the See also:anchor down. Additional information and CommentsThere are no comments yet for this article.
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