"I T now remains for me to tell you about the principal weaves of cotton. First there is percale, which has a firm and close texture and a smooth surface, and is much used for shirts, curtains, covers, and sometimes for table and bed linen. Ornamented with colored designs, it is also used for dresses.
"Percale, diminutive of percale, as its name shows, is a fabric of inferior quality and of transparent texture, being very loosely woven. Its thread is flat and its surface fluffy and plush-like, whereas in percale the thread is round and the surface smooth. It lacks firmness and does not last long. It is used chiefly for lining.
"Common calico is less fine, less firm, and cheaper than percale, but is used in general for the same purposes.
"Muslin is a very fine, soft, light material, the most delicate of all cotton goods. There are some muslins that for fineness almost rival the spider's web, and of which a piece several yards long could be contained in an egg-shell. Among muslins are classed nainsook, organdie, and Scotch bastiste.
"Cotton has a decided superiority over flax and hemp in
that it readily takes any desired color or ornamental
design, the dyes being quickly absorbed,
lastingly retained, and shown off to the best
advantage. Who does not know these admirable goods in
which the most varied and brilliant colors are
artistically combined and our garden flowers are
reproduced in astonishing perfection? Some of these
prints are decorated with flowers such as no garden
could furnish. Cotton alone lends itself to this
richness of coloring, hemp and flax being absolutely
inadequate. Cotton goods ornamented with colored
designs are called prints, and they first came from
India, where their manufacture has been known for a
very long time.
"First the fabric is bleached with the greatest care so that no dinginess of its own shall dim the brightness of the colors to be received. Energetic washing, over and over again, and the powerful bleaching agent I have just spoken of, namely chlorine, make the cotton perfectly white.
"Now comes an operation that would fill you with astonishment if you happened to see it: it is the operation of singeing. I must tell you to begin with that all cotton thread, however perfect the spinning machine producing it, is covered with a short down or fluff consisting of the tip-ends of the vegetable fibers standing up by their own elasticity. At the time of weaving this fluff is laid flat by means of a preparation of glue, so as to leave perfect freedom for the play of the shuttle; but now this preparation, which would greatly interfere with the setting of the colors, has disappeared to the last trace, and the fluff of the threads stands up free again. Well, on such goods, all bristling with tiny filaments, the colored designs would not take well; there would be unevenness of tint, ill-defined outlines; cracks and seams, in fact. The surface must be as clean and smooth as a sheet of paper. It would be well-nigh impossible to obtain with shears such as are used for shearing woolen cloth a surface as smooth as the subsequent operations demand. Accordingly it is the custom to have recourse to the use of fire. The material is passed with the necessary rapidity before a broad jet of flame, which thoroughly burns off every bit of fluff without in the least damaging the fabric itself. Nothing is more extraordinary to the novice than to see a piece of calico or percale or even muslin passing through the menacing curtain of flame without catching fire."
"And who would not be surprised!" exclaimed Marie. "I should think the delicate fabric would certainly catch fire."
"You would think so, but there is no danger if the material passes quickly along and does not give the heat time enough to penetrate beyond the fluff. Let us dwell a moment on this peculiarity, which will enlighten us concerning a very remarkable attribute of cotton.
"You know what happens when you put the end of a piece of cotton thread into the lamp flame. The part thrust into the flame is consumed at once, but the fire spreads no farther and goes out just at the point where the thread ceases to be enveloped by the flame. With a piece of linen or hemp thread the result would be a little different: the thread would continue to burn more or less beyond this limit. That is on account of the different manner in which cotton on the one hand and flax and hemp on the other act under the influence of heat. Cotton is rather impervious to heat: flax and hemp, on the contrary, offer only feeble resistance to its spreading. I will not say any more on this point now, but will return to it some day with the necessary details.
"The few facts I have given you are sufficient to explain what takes place in the singular operation of singeing. If the fabric passes through the fire quickly and at an even rate of speed, the flame envelops it on both sides and even traverses the meshes, burning off all the fluff without injuring the threads themselves, because the heat has not time to spread further.
"To banish once and for all your incredulity in regard to this singeing process I will show you an experiment which, indeed, has no close connection with the calico-printer's art, but which illustrates the different degrees of inflammability possessed by different substances. What should you say if I were to tell you that live coals can be placed on the finest muslin without burning it in the least?"
"I should say, 'Seeing is believing,' " answered Claire.
"Then you shall see, Miss Incredulous. Take a piece of muslin, as fine as you please, and wrap it tightly around once of the brass balls that ornament the top of the stove. Tie it securely underneath with a string so that the muslin will touch the metal in every part. Now take from the open fire a live coal and apply it with the tongs to the muslin that covers this kind of doll's head."
Claire followed these directions with scrupulous care: the live coal was touched to the muslin, and, greatly to the surprise of all the children, the delicate fabric remained perfectly intact.
"Go still farther," commanded Uncle Paul. "Take the bellows and make the live coal burn as brightly as you like, letting it rest on the muslin while you do so."
Claire worked the bellows, the coal became red-hot all over, and still the muslin underwent no change, appearing to be quite incombustible.
"Why, this is unbelievable!" she cried. "How is it that muslin can stand the touch of a live coal without burning the least bit?"
"What protects it from the fire," replied her uncle, "is the metal underneath. The brass, a substance easily penetrated by heat, takes to itself the heat of the coal and leaves none for the muslin, which is much harder to heat. But if the delicate fabric were by itself, it would burn at the first touch of the live coal."
Several times during the day Claire repeated this experiment by herself, each time more astonished than before at this strange incombustibility.