Protractor

“ Protoloma: the anterior margin of primaries.
Protomesal: applied to certain areolets in Hymenoptera, situated between costal cells and apical margin.
Prototergite: the foremost dorsal segment of abdomen.
Preto-thorax: = prothorax: q.v.
Prototype: a primitive form to which later forms can be traced.
Protractor: that which extends or lengthens out: applied to muscles.
Protuberance: any elevation above the surface.
Protuberant: rising or produced above the surface or general level.
Proventriculus: the posterior portion of crop: the gizzard. ”

“ Then there was the brass protractor. It is true there were no inches marked on this; but the workman who made it would naturally follow some standard, and the chances were very great that the diameter of this instrument would be found to be an exact multiple of the inch, and as I conjectured, exactly four inches. To test this matter I laid the protractor on the short side of one of the plates, and taking the difference between the two found, as I had expected, that this difference was one fifth of the width of the plate, and one seventh of its length. ”

“ At the upper ends the strips were spread to receive the blocks on the tripod head. In this position they were held by headless wire nails driven into the ends of the blocks and fitting into holes drilled in the strips. For a 76 plumb line we
Fig. 75. The Surveying Instrument Complete. tacked a cord to the center of the tripod head, and attached a good-sized sinker to its lower end. In connection with this plumb line we occasionally used a protractor consisting of a semicircle of cardboard 5 inches in diameter, on which the degrees of the circle
Fig. 76. The Protractor. ”

“ The spindle, from the crescent shape of the second prothallial cell, assumes a position at an angle to the major axis of the prothallus, the lower nucleus and end of the spindle being crowded to one side by the position of the first prothallial cell, while the upper nucleus occupies a central position in the upper half of the cell which, when the new wall is formed, will become the central cell. The lower nucleus, which becomes the nucleus of the stalk cell, is already in this early stage noticeably smaller than the upper nucleus. ”

“ The truth is just this, that the measured and mixed gases, the vessel, and the spark, in the one case, are as unlike the fortuitous food, the living organs, and the long process of assimilation in the other case, as the product water is unlike the product protoplasm. No; that the action of the electric spark should be unknown, is no reason why we should not insist on protoplasm for protoplasm, on life for life. Protoplasm can only be produced by protoplasm, and each of all the innumerable varieties of protoplasm, only by its own kind. ”

“ The energy of each, whatever be its particular mode, has its source in the breaking up of the protoplasm. Chemical changes, including the assumption of oxygen and the production, complete or partial, of carbonic acid, and therefore also entailing a certain amount of secretion and excretion, must take place in each and every tissue. And so with all the other fundamental properties of protoplasm; even contractility, which, for obvious mechanical reasons, is soonest reduced where not wanted, is present in many other tissues besides muscle. ”

“ It is, of course, the ambition of the physiologist to make protoplasm, but so far he has got no further than making some of the complicated bodies into which protoplasm breaks up when it dies. A little while ago this bare possibility was loudly derided, but the advance in organic chemistry has been so great of late years, and so many complicated substances which once seemed as unobtainable as protoplasm itself have been made in the laboratory, that we now have hope of a precise knowledge of the chemistry of life some day, though that day may be yet very distant. ”

“ Here the vegetative filament puts out two protuberances, which become shut off from the body of the filament by partitions. The protoplasm in one of these protuberances arranges itself into a round mass--the oosphere or female cell. The protoplasm of the other protuberance divides into many small masses, furnished with cilia, the spermatozoids or male cells. Each protuberance bursts, and some of the spermatozoids come in contact with and are absorbed by the oosphere, which then secretes a cell-wall, and after a time germinates. ”

“ Our syringe has a screw fitting turned on the suction end so that any of the tubes or the Gas-trocar can be fitted on and collections of fluid in the body pumped out with it.
All the tubes and the Gas-trocar are nickel plated and non-corrosive, and we would call especial attention to our improved Gas-trocar which is the most complete tool of its kind ever manufactured being superior to any other as it is so constructed that it will not clog. ”

“ Only serum and plasma which are absolutely free from hæmoglobin must be used for these experiments. To a measured quantity of serum or plasma a certain quantity, in cubic centimetres, of an albumen, peptone, or polypeptide solution, having a known composition in regard to substrates, is added; a polariscope tube is filled with the mixture, and the rotation is quickly ascertained by means of a good polariscope. The tube is then placed in an incubator, and from time to time the angle of rotation is again noted. ”

“ We have seen how little mere form has to do with the essential properties of protoplasm. This may shape itself into cells, and the cells may combine into organs in ever-increasing complexity, and protoplasm-force may be thus intensified, and, by the mechanism of organization, turned to the best possible account; but we must still go back to protoplasm as a naked, formless plasma if we would find—freed from all non-essential complications—the agent to which has been assigned the duty of building up structure and of transforming the energy of lifeless matter into that of living. ”

“ The Protista that live in water undergo a death by "diffluence" or "granular disintegration" on being wounded, crushed, or sometimes after an excessive electric stimulation, or contact with alkalies or with acids too weak to coagulate them. In this process the protoplasm breaks up from the surface inwards into a mass of granules, the majority of which themselves finally dissolve. If the injury be a local rupture of the external pellicle or {15}cuticle, a vacuole forms at the point, grows and distends the overlying cytoplasm, which finally ruptures: the walls of the vacuole disintegrate ”

“ There can be no direct communication between protoplasm and a steam-engine; there may be and often is direct communication between machines of even the fifth order and those of the first, as when an engine-man turns a cock, or repairs something with his own hands if he has nothing better to work with. But put a hammer, for example, to a piece of protoplasm, and the protoplasm will no more know what to do with it than we should be able to saw a piece of wood in two without a saw. ”

“ But no man on earth except myself has ever been able to create a proteid. They have missed the whole secret because they have been working at ordinary temperatures. Just as the drop of water will not form from its two gases at 4,500 degrees Fah., nor at its own lower explosion temperature, unless the spark be added, so will protoplasm not form except under certain electric and thermal conditions. ”

“ There is no doubt that the protamines of one type or another are integral parts of every proteid molecule, and when their chemical constitution is made quite clear, much will have been accomplished toward a fuller understanding of the more complicated forms. ”

“ Flagellar rotation can be driven by protons or sodium ions. The proton- and sodium-driven motors are separate and can coexist in the same cell. Both probably evolved early in flagellar evolution as posibacteria and Gracilicutes have both types. Both have two components: an ion channel (MotA or PomA respectively) in the cytoplasmic membrane, which associates with ancillary proteins and the outside of the bacterial rotor so as to drive it; and a protein that binds to the ion channel and attaches it rigidly to the murein cell wall to prevent it from rotating (MotB or PomB [83] ) . ”

“ A second agent must first of all make them capable of their respective functions—just as a hammer without a handle, or a screw without a screwdriver, are only useful when the missing parts are at our disposal. These agents are probably supplied by the cells of other organs. ”

“ The study of moneric protoplasm has disclosed that so-called contractility is not merely a property of the living substance, but that it is its function, stimulated by the dynamical influences of the medium, and effected by means of chemical disintegration. The organic molecule, before it experienced its chemical, its functional rupture, was held together by the bond of inwrought chemical affinities. ”

“ A proton, and perhaps an electron, would be an association of such primates, superposed on each other, with their frequencies and spatial dimensions so arranged as to promote the stability of the complex organism, when jolted into accelerations of locomotion. 188The conditions for stability would give the associations of periods possible for protons. The expulsion of a primate would come from a jolt which leads the proton either to settle down into an alternative association, or to generate a new primate by the aid of the energy received. ”

“ In presence of such powers displayed by matter of simple kinds we shall see how impossible it is even to imagine those processes going on in organic matter out of which emerges the dynamic element in Life. As no separate form of proteid possesses vitality, we seem obliged to assume that the molecule of protoplasm contains many molecules of proteids, probably in various isomeric states, all capable of ready change and therefore producing great instability of the aggregate they form. ”

“ We shall now examine the structure and behaviour of protoplasm and of the cell as an introduction to the detailed study of the Protozoa, or better still Protista, [2] the lowest types of living beings, and of Animals at large.
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It is not in detached fragments of the tissues of the higher animals that we can best carry on this study: for here the cells are in singularly close connexion with their neighbours during life; the proper appointed work of each is intimately related to that of the others ”

“ So long as adjacent cells with their contents are subject to equal pressures no tendency to redistribution of the protoplasm exists, and there may then occur the action sometimes observed inside the strands within a cell: currents with their contained granules moving in opposite directions. But if the cells forming a portion of tissue are subject to greater pressure than the cells around, their contained protoplasm must be forced through the connecting threads into these surrounding cells. Every change of pressure at every point must cause movements and counter-movements of this kind. ”

“ We have seen how it is always changing, always taking in food, always giving off waste materials. We have seen, too, that it grows and that it does work, and that in a large mass the cells which compose it share the labour instead of each component cell performing all the vital functions. We have now to consider the work which protoplasm does—in a word, the mechanical effect of the chemical actions just described.
The simplest movement of protoplasm is to be seen by the aid of the microscope in certain vegetable cells, where granules seem always streaming about in different directions. ”

“ Roal's eyes dreamed. In human eyes there was always the expression of thought that machines never show.
"Hydrogen, an atom in space; but a single proton; but a single electron; each indestructible; each mutually destroying. Yet never do they collide. Never in all science, when even electrons bombard atoms with the awful expelling force of the exploding atom behind them, never do they reach the proton, to touch and annihilate it. Yet—the proton is positive and attracts the electron's negative charge. ”

“ All Protista have a soul—that is to say, are “animate”—as well as all animals and all plants. The soul’s activity in the Protista manifests itself in their irritability, that is, in the movements and other changes which take place in consequence of mechanical, 69 electrical, and chemical irritation of their contractile protoplasm. Consciousness and the capability of will and thought are probably wanting in all Protista. ”

“ If not too much of the toxin is given, instead of injuring, it acts as a chemical stimulus to the cell in the manner already described. The cell in response produces more of the specific thing, which in this instance is more receptors which can combine with the toxin, i.e., with its haptophore group. If the stimulus is kept up, more and more of these receptors are produced until an excess for the cell accumulates, which excess is excreted from the individual cell and becomes free in the blood. ”

“ Hence the implication is that a proteid-molecule contains thousands of units, of which the different classes have their respective rates of inconceivably rapid oscillation, while each unit, receiving and emitting ethereal undulations, affects others of its kind in its own and adjacent molecules: an immensely complex structure having immensely complex activities. And this complexity, material and dynamic, in the proteid-molecule we must regard as raised to a far higher degree in the unit of protoplasm. Here as elsewhere alternative impossibilities of thought present themselves. ”