Comb (anatomy)

“ Sometimes the weakening is inappreciable—when the comb is essentially single; sometimes it is great, and the result is a comb in which the median element is reduced to one-half; sometimes, finally, the determiner of median comb is so completely weakened by its dilution with "no-median" as not to be able to develop, and we have the cup comb with only a trace of the median element. Nevertheless, such a cup comb is heterozygous and produces both single-combed and Polish-combed germ-cells. ”

“ This has the effect of breaking the wavy combing into short and long straight bits, similar to the pores or grain of the real wood. Both the first and second combing may be varied by holding the comb in a slanting direction, and may be fine or coarse, according to the width of the combs used; now take a soft rag folded, and with this partially clear off the grain which runs over the figure, leaving only a sufficient quantity crossing the light or figure, to be just distinguished, exactly as it appears upon the figure in real oak. ”

“ Indeed, the imitation is so perfect in the best classes of stained combs, that a practised observer can only detect it. We were shown, for example, two specimens of braid-combs, one of real tortoise-shell and another of stained horn; and so much alike were they in color and configuration, that we could not tell which was which, and yet the one comb was worth about ten times as much as the other. This operation of staining, which is somewhat artistic, is performed by women. ”

“ When he finds a simple geometrical construction, for instance in the honey-comb, he would fain refer it to psychical instinct or design rather than to the operation of physical forces; when he sees in snail, or nautilus, or tiny foraminiferal or radiolarian shell, a close approach to the perfect sphere or spiral, he is prone, of old habit, to believe that it is after all something more than a spiral or a sphere, and that in this “something more” there lies what neither physics nor mathematics can explain. ”

“ A thin steel saw bow, mounted in an iron or wooden handle, is the implement used by the comb-maker to cut the bone, ivory, and wood into slices of from a twelfth to a quarter of an inch thick, and of a size suitable to that of the comb. The pieces of tortoise-shell as found in commerce are never flat, or, indeed, of any regular curvature, such as the comb must have. They are therefore steeped in boiling water sufficiently long to soften them, and set to cool in a press between iron or brass moulds, which impart to them the desired form which they preserve after cooling. ”

“ It is impossible. How can you conceive the edge of space? Something must be beyond—something or nothing, and even that would be more space, wouldn't it?"
"Gosh," said the Very Young Man, and lighted another cigarette.
The Chemist resumed, smiling a little. "Now, if it seems probable that there is no limit to the immensity of space, why should we make its smallness finite? How can you say that the atom cannot be divided? As a matter of fact, it already has been. The most powerful microscope will show you realms of smallness to which you can penetrate no other way. ”

“ The nucleus is all the comet's solid matter, a mass of meteoric and other material hanging in the hollow at the coma's center. The great coma blows from its own electrical energy, and is driven through space by the release of some of that energy backward, through the vast tail, which is simply released energy from the coma. It is the great coma that makes a comet deadly to approach, since any matter that enters its terrific sea of electrical energy is converted instantly into electrical energy likewise, changed from matter-vibrations to electrical-vibrations, annihilated. ”

“ The Chemist's voice came to him from far away. "We are all of us here in a world that only occupies a portion of one little atom of the gold of a wedding-ring. Yet what you see there in that stone——"
The Very Young Man raised his head. Before him stood the microscope, with its fragment of stone gleaming in the blue light of the burning wire. ”

“ A single needle is not relied upon to secure the direction of the card, the latter being attached to a system of four or even more magnets, all pointing in the same direction. The compass must have no iron in its construction or support, because the attraction of that substance on the needle would be fatal to its performance. ”

“ This is evidently due to the fact that the coma immediately around the nucleus was so bright as apparently to form a part of it at considerable distances from the sun. G. P. Bond estimated the diameter of the actual nucleus at 500 m. That the nucleus is a body of appreciable mass seems to be made probable by the fact that, except for the central attraction of such a body, a comet would speedily be dissipated by the different attractions of the sun on different parts of the mass, which would result in each particle pursuing an orbit of its own. ”

“ We have seen that a well-developed comet of the normal type usually comprises a nucleus, a head or coma, and a tail. Comets which have no tails generally exhibit heads of very simple structure; and if there is a nucleus, the nucleus is little else than a stellar point of light. But in 160 the case of the larger comets, which are almost or quite visible to the naked eye, the head often exhibits a very complex structure, which in not a few cases seems to convey very definite indications of the operations going on at the time. ”

“ But then they found that an atom was no more a solidity than the molecule, or the iron bar. Still other spaces, with other vibrating particles. And fatuously they said: ‘We have found electrons, revolving around a central nucleus.’ But that meant nothing, and at last they began to realize it.
“Let your mind leap beyond all that, Leonard. It is too fatuous to think that each division of matter is the last, simply because you cannot make another division. Let’s go back to that original vortex of nothingness. It created an apparent solidity, exactly as the vibrating molecules of iron create iron. ”

“ Happily this does not hinder us from finding out by what law these forces act, and how they enable us to navigate the ocean. I therefore hope the reader will be interested in a short exposition of the very curious and interesting laws on which the science of magnetism is based, and which are applied in the use of the compass.
The force known as magnetic, on which the compass depends, is different from all other natural forces with which we are familiar. It is very remarkable that iron is the only substance which can become magnetic in any considerable degree. ”

“ What, then, was this primary matter on which motion first acted, and before motion had by various ‘modes’ produced in it a single quality? No answer is possible; but, nevertheless, as the philosophy unfolds itself we find that ‘we need not refrain ... from dealing with matter as made up of extended and resistant atoms,’ [9] and henceforth we are led to consider the cosmic nebula as not only homogeneous, but as being, in its homogeneity, atomic. [Pg 24]
No lover of physical and chemical science can do other than profoundly admire the atomic theory of modern physics. ”

“ Matter may pass back into the ether and still be matter. It can hold its identity only through its cohesion. The ions of cohesion and adhesion are the forces that control: they are at the bottom of all life and substance, of all that man calls matter. Be it iron or flesh, matter can hold its identity only through its cohesion; and there is nothing so small or so great but what has its identity. The Universe has it. Infinity itself must have identity, at least intrinsically. Everything must have its ions. You have guessed right. A comet is an ion. ”

“ One other property of the double object-glass remains to be mentioned, which is, that when the longer aplanatic focus is used, the marginal rays of a pencil not coincident with the axis of the glass are distorted, so that a coma is thrown outwards; while the contrary effect of a coma directed towards the centre of the field is produced by the rays from the shorter focus. These peculiarities of the coma seem inseparable attendants on the two foci, and are as conspicuous in the achromatic meniscus as in the plano-convex object-glass. ”

“ This whole universe of stars, merely a cluster of tiny particles, clinging together to form an atom of something else! And trillions of such atoms making up the head of a pin, lying on someone’s bureau!
Dr. Weatherby’s voice quieted. “Suppose ultimately, we were to cross our atom and emerge in exactly the wrong direction. We would find no vastly great emptiness, but merely other atoms like our own, going downward, so to speak, into the pin’s head, instead of merging from it.
“But that cannot happen. Nature, in all its natural phenomena, always chooses the path of least resistance. ”

“ Our solar system is nothing but an atom. I am an astronomer. On the Earth, I held that we would never solve Infinity through our telescopes. Better, I said, that we study our own atom. Afterward, we might be able to find our way out. I held that a comet is but an ion of cohesion or adhesion, as the case may be, with a function exactly analogous to the ions that hold together the atoms of this pencil. I would solve the comet and get at its secret. I came in an ether ship. When I reached the nucleus I found the gap in the rim. ”

“ By simply pressing a lever you will loosen an atomic current that will blow out the channel. The lake will drop down and rush into the rim. That will be all. The comet will no longer be cohesive. It will be a mad ion, a bit of heat, energy. It will pass to the surface of the substance, to the outside of the Universe.
"' "But the heat?" I asked, "such a speed is unknown. The nucleus would burn."
"' "Not at all. You cannot destroy an ion. You merely loosen it. The nucleus will be protected by its own coma. You will not notice its speed." ”

“ However slight gravitation might be between some of the grains, if it existed at all, or was unopposed by some other force, with sufficient time--and they have eternity--every comet would come together like a planet into one solid mass. Perhaps some similar force maintains gases in the distended tail, though I know of no such, or even any analogous manifestation on earth. If the law on which we have been brought up, that 'every atom in the universe attracts every other atom,' were without exceptions or modifications, that comet could not continue to exist in its present form. ”

“ It frequently changes very much in size during the period of the comet's visibility. The nucleus is the only part of a comet's structure which has even the most distant claim to solidity; but even so the evidence which has been gradually accumulated all goes to show that while it may be solid in the sense of being composed of particles which have some substance, it is not solid in the sense of being one coherent mass, but rather consists of something like a swarm of small meteoric bodies. Surrounding the nucleus is the coma, from which the comet derives its name. ”

“ Stars no longer. Why, these were mere imponderable electrons! Some were dark, shining only by reflected light-worlds like our earth. But I knew they were not imponderable bodies passing through the density of our vehicle. The reverse.
It was we who were the less dense. Our vehicle comparatively was a puff of vapor, through which these tiny bodies were passing.
A stream of electricity, myriad electrons flowing through a copper wire, are not less dense than the wire. The electrons are the densities; imponderable, of a mass imperceptible, because they are infinitely small. ”

“ In order for you to understand just what happened, and why Amba was not destroyed when he pressed the buttons that started the atom bombs on their journeys of destruction, I must tell you a little of the basic nature of reality. Our universe is at all times and in every respect a root of a cubic equation. It has long been known that space is curved. ”

“ Whether the inertia of matter has or has not a complete electromagnetic explanation is a question that it will perhaps take many years to answer with any degree of certainty. The experiments of Kaufmann seem to prove that in the case of a single electron the mass is entirely of this origin ”

“ Now the negatively charged corpuscles are preeminently fitted to serve as nuclei for the condensation of the ordinary matter. Hence those particles of the latter which, having more than the critical diameter, fall back to the sun, will carry back a negative charge to him; while those which have less than the critical diameter will carry a negative charge off into space. On both counts the corona will be left with a surplus of positive charge. The same arguments hold for the vapors emitted by the nucleus of a comet. Thus comets' tails should consist of negatively charged particles. ”

“ On the first of these dates the sodium-lines were still easily visible, though not conspicuous. The carbon bands were magnificent, especially the brightest one (in the green) , in which could be clearly seen the three fine lines observed in the spectrum of Coggia's comet. The band in the violet was very faint. The nucleus gave a strong continuous spectrum, on which the carbon bands were superposed; and in the tail the proportion of white light (continuous spectrum) to carbon light appeared to be about the same as in the nucleus. ”

“ The physicist therefore concludes—warning us that on this further point he is drawing a theoretical conclusion—that the atoms of ordinary matter are made up of electrons. If that is the case, the hydrogen atom, the lightest of all, must be a complex system of some 1700 electrons, and as we ascend the scale of atomic weight the clusters grow larger and larger, until we come to the atoms of the heavier metals with more than 250,000 electrons in each atom. ”