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been able to procure so secret and im- Japanese who employed him. He said portant a document. The captain who the trial was over, he would take his had been in charge of the defense came punishment, and he wanted to be let up and apologized. He said he had been alone. He even refused to appeal. He fully convinced of Katzan's innocence, simply said to the court:that the latter had sworn to him by the 'I am satisfied with the sentence. I memory of his mother that he was not expected twelve years, and I get only guilty but was the victim of a frame-up. four.'

That settled Katzan. I need only This matter settled, and the morale add that after the trial he refused to and prestige of my office somewhat give any further information regarding restored, I now proceeded to follow up his work as a spy, or to name the the case against Siraisi.

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He was a big, powerful man, the sort As the descent began he gasped for of man generally described as a 'typical breath and clutched my arm. guardsman.'

The cage stopped, and we stepped He had wandered much. He had out. A few minutes were spent explainseen men work at many occupations ing the mysteries of haulage ropes and tea planters in Ceylon and China, gold roadways; then we started for the face. miners on the Rand, diamond miners at ‘Now keep your back well bent; it's Kimberley, cowboys in the Wild West, only four feet high, so be careful!' lumberjacks in Canada. . . . He had

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We tramped steadily. He stumbled; seen men build ships and make cotton his eyes were unaccustomed to the faint and woolen goods, and he had sailed in light of a safety lamp. “Ugh; wait a a tramp steamer. He had soldiered minute! Ugh, my head!' He failed to through the war and risen to the rank keep his head low enough, and hit a of colonel; but he confessed he had baulk. I turned round. The perspiranever seen an electrically driven coal- tion was streaming down his face, his cutting machine working in a twenty- breathing was labored, and we had only

gone four hundred yards. We halted a He was anxious to see one. Our few minutes; I warned him to stoop manager granted permission, and he lower, and away we went again. . came to see. I met him at the pit-head. At last we arrived at the deputy's He was dressed for the occasion in a place, and I handed him a pair of leathsuit of mechanic's overalls. With er knee-pads. "What are these for?' he eighteen others we got into the cage. asked. I fixed them for him, explaining 1 From the Daily Herald (London Labor

that they were to protect his knees daily), May 3

when creeping. 'Are we going to creep?'

inch seam.

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'Yes.' 'Ugh! Is it far?' 'No; keep along. 'Let's get out of this,' pleaded your back well down and follow our visitor. So out we got, back to the me.'

deputy's ‘kist,' offed with our knee‘Here we are. That's the face. Now pads, and made our way to the shaft. get down, and we'll crawl along to The visitor reeled like a drunken man where the coal-cutter is working.' His head hit the roof. Down went his

With great difficulty he got into the head and up went his back. “Ugh!' and twenty-inch-high passage, and he fell on his knees. Out went his lamp. dragged ourselves along. Men were One lamp between two of us. After working stripped to the waist and many stops we arrived at the shaft, and bathed in perspiration. One stopped then up into the fresh air. With great the machine and explained how it difficulty he stretched himself erect. worked. We pulled ourselves back a His back ached, his head ached, his little. “Right; set her away!' The knees ached, he felt awful. ‘Oh, is n't power was switched on, and the ma- the fresh air grand?' he cried. chine began working.

I asked him what he thought of it Flying coal dust filled the air till you all. His answer came like a burst of could not see. The stench of heating oil thunder: 'It's like Hell! Absolutely and the sweat of human bodies made the rottenest job I ever saw. I am sorry it almost impossible to breathe. The for those fellows. I wonder they stick Colonel coughed and spluttered as the it. Fancy sticking a job like that for coal dust got into his throat. The roof ten shillings a day! It's a rotten job.

weighed,' the supports creaked, the Absolutely rotten!' coal cracked like rolls of thunder.

I don't think he'll want to see a coalThe scene was indescribable. We cutting machine at work in a twenty

. half crawled, half dragged ourselves inch seam any more for a while.

EPITAPH ON A DISUSED SUNDIAL

BY ARCHIBALD Y. CAMPBELL

[London Mercury]

STRANGER, time passes; ask not how.
I was a

dial
once;

but

now,
My crown is defaced by years of rain,
As my own tombstone I remain,
To testify that in this place
Stood once one of that gentle race
Whom their own shape and choice empowers
To number only sunlit hours.
He who too long does nothing, dies.
Lie light upon me, English Skies!

THE RIDDLE OF CELLULOSE 1

BY PROFESSOR DOCTOR EBNER

No other substance is receiving so much the most powerful microscope, arranged attention from the physical chemist to- in symmetrical patterns so that their day as cellulose. This is not only the internal structure resembled that of chief structural material in all plants, crystals, although they might assume but it is also the raw material of new various outward shapes. While most and important industries. Notwith- chemical substances, like salt, sugar, and standing the patient study that has the like, separate into their individual been devoted to it, however, its chemi- molecules in water, the colloids cannot cal structure and composition still do this, but simply separate into present many puzzles.

these tiny molecular aggregations, or Cellulose has two qualities that ren- micella, which are the lowest subder the investigation of its physical and divisions of which they are capable chemical constitution especially diffi- while retaining their collodial identity. cult: it is insoluble in water or other Nägeli's researches, however, could ordinary solvents, and it is extremely be pursued only to a certain point for sensitive to the action of acids and lack of the technical instrumentalities saline solutions. These qualities make necessary for further investigation. it almost impossible to determine from The next advance had to wait upon the products of its decomposition what later discoveries, and only within the the form of its original constituents past few years has the nature of these was. To be sure, cellulose shares this molecular groups, or primary particles, incapacity for molecular dispersion of the cellulose structure been fully with several other organic substances, established. The first step forward like albumin, starch, and certain pig- followed the discovery that cellulose ments, which are classified together refracted light in the same way that under the collective name of colloids. crystals do

crystals do — for instance, the cell The first investigator whose patient walls of a flax fibre produced a refracstudies

gave him some insight into the tion six times that produced by quartz. spacial structure of the colloids and It was shown further, by saturating their so-called solutions was Karl von the cellulose with water, that this Nägeli, whose researches into the con- double refraction was not due to the stitution of starch in the late fifties of fact that the tiny rod-groups, or micelthe last century convinced him that all læ, were embedded in a medium of colloids were made up of minute crys- different refractivity from itself, but talloid bodies which he called micellæ, that the micellæ themselves had a or 'little crumbs. These he assumed to distinct refractive index, such as had be extremely diminutive groups of hitherto been assumed to be peculiar molecules, too small to be visible under to microscopic crystals. 1 From Rölnische Zeitung (Conservative daily),

This led to the conclusion that celluApril 22

lose must consist of minute rodlike

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crystals connected in series, and that micellæ lying with their axes parallel to this stringing together of the minute the axis of the fibre itself, that is not rods, and the parallel grouping of the true of artificial cellulose, mercerized strings, persisted even throughout a cotton, and most kinds of artificial great number of chemical changes in silk. The latter have their crystals the cellulose itself. For example, the lying pell-mell in all directions, and an rodlike structure of the micellæ was X-ray photograph of them shows not affected when cellulose was treated alternating dark and light lines in with nitric acid and thus converted closed circles. into guncotton.

Very recently it has proved possible, These conclusions were brilliantly by employing certain methods of drawconfirmed when the X-ray was applied ing and tension when the cellulose is to the investigation of fibres. In 1920 leaving the copper-ammoniac solution, ramie, an almost pure form of cellulose, to produce an artificial silk whose was discovered to produce an X-ray crystalline structure as shown by its photograph of a kind previously ob- X-ray photograph is the same as that served only in case of crystals. For of natural cellulose. In other words, its example, while noncrystallized, or so- rodlike, crystalloid micellæ all have called amorphous, substances produce their axes lying in the same direction. simply a black blur on a Röntgen plate, The displacement, or jumbling-up out crystals and crystalline bodies produce of their normal parallel order, of the a number of alternating bright and dark crystals in ordinary artificial silk excurved lines called interference lines. plains why this substance reacts so The appearance and strength of these much more readily to chemicals, and lines bear an intimate relation to the absorbs water and colors so much more inner structure of the crystal — the quickly, than natural fibres. Its comso-called crystal grating. In case of ponent crystals lie in all directions, ramie fibres, these interference rings leaving interstices and exposing a were not, to be sure, complete, but fell larger surface to foreign ingredients into definite symmetrically arranged like pigments and moisture. On the points or short segments of circles. other hand, the end-to-end arrangePolanyi, who in 1921 made an exhaus- ment of the micellæ in parallel lines tive investigation of these Röntgen, that exists in natural fibres is easy to four-point patterns, or fibre diagrams, understand, for it is necessary, not only showed that they appear only when the for the upward growth of the plant, but innumerable tiny crystals that form a

in order to give the plant greater recrystalline substance all lie with their sistance to wind, weather, and other axes in the same direction, instead of external influences. in different directions. Such an ar- While the origin of the crystalloid rangement of these crystalloids in par- structures now assumed to make up allels is characteristic of the structure every fibre is not definitely known, it is of all fibres - not only of ramie, but very probable that they do not exist cotton, silk, wood fibre, and all similar in the young plant or animal from the substances of vegetable or animal beginning, but are developed from an origin, including hair, muscles, and amorphous jelly. Young asparagus, for

example, and the chitin of insects in But while natural cellulose in the the chrysalis state, are still structureform of ramie, cotton, flax, and other less, and consist of an incompact, similar fibres, has all its crystallized watery substance that is later converted

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into a firm crystalline composition. producing it was. Investigations show We may infer that drawing and tension that this product consists mostly of play the same part in the formation of unchanged or very slightly changed the fibre here that they do in the cellulose. X-ray photographs show that latest processes of producing artificial hydrocellulose has practically the same silk. Drawn-metal wire, which likewise Röntgen diagram as ordinary cellulose. consists of minute crystalline rods and We are thus led to infer that acids do consequently produces the same Rönt- not affect the tiny crystalline rods or gen diagrams as natural cellulose, gives micellæ themselves, but only the binder us a hint to this effect, and confirms between them, and that their effect is the inference that vegetable fibres are simply to allow these rods to fall apart. crystallized from some amorphous This isolation of the crystalline material.

bodies is important in its bearing upon This assumption has been strength other chemical transformations. We ened by the results of recent investiga- have already mentioned that when tions in natural silk-fibrine and chitin, cotton is converted into guncotton, or which play the same part in the animal nitrocellulose, the outer form of the structure that cellulose does in the fibres is not changed. All that occurs vegetable structure. In all these differ- is an internal transformation, or pseuent organic compounds, both vegetable domorphosis, of the tiny crystalloids. and animal, an identical crystalline That is, the chemical reaction occurs in substance has been discovered em- each of these crystalloids individually, bedded in certain adhesive materials while it is kept in its original position which chemists have for a long time by the binding substance. Very recent designated as mucilages, or semicellu- researches show that when cellulose ablose, without knowing their exact sorbs water the latter is taken up by constitution. Unless there were some the binder between the micellæ, and such intermediate substance, cellulose not by the crystalloids themselves. itself would not possess sufficient re- What we have said of the structural sistance to wind-pressure and similar character of fibres, as consisting of forces to perform its functions in plant minute micellæ, or rodlike crystalloids and animal existence. For if the tiny arranged parallel and end-to-end, which crystalline rods were in direct contact, we can now assume to have been defitheir size and shape would be easily nitely demonstrated by the X-ray, fully modified by external accident and the explains two characteristics which disstrength of the cellulose fibre would be tinguish cellulose from other organic seriously weakened.

substances — its tensile strength and This binder or cement in cellulose its chemical inertness. But when we is much more easily attacked by extend our inquiries to the ultimate chemicals than the crystals themselves. component of these crystalloid formaEvery laundryman knows how quickly tions, to the primary parts of the textile fibres are affected by mineral micella, we immediately encounter new acids, which weaken them so that difficulties which have not yet been they will rub to pieces between the solved. We are practically certain that fingers. Chemists have hitherto called the ultimate constituents of the micella the product resulting from the action must be a grape-sugar residuum conof such acids upon cellulose hydrocel- sisting of six atoms of carbon, ten atoms lulose, without being able to describe of hydrogen, and five atoms of oxygen. exactly what the chemical reaction The presence of these grape-sugar or

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