Taking the whole world together there is perhaps no one article more extensively used than the lead-pencil, and, aside from the steel-pen, there is probably no single article that contributes more to human progress. In even the most ancient manuscripts we find marks resembling those of a hard lead-pencil, but a little research leads to the discovery that the ruled lines were made with sharp-edged disks of lead, and not by an instrument like a pencil. The use of black and red chalks dates to the fourteenth or fifteenth centuries. During the reign of Queen Elizabeth, in the year 1564, the black-lead mines of Burrowdale, County of Cumberland, England, were discovered, and the following year black-lead-pencils were made in substantially the same form as we use them at the present day.
Black-lead, graphite, or plumbago is a mineral form of carbon, with a slight mixture of iron. Of great value in the arts and extensively used, yet, from its great abundance, only the finer and purer qualities find a ready market. The discovery of the Cumberland lead, as it is called, was most valuable. The manufacture of pencils from it at once became exceedingly important, and the English government deemed it necessary to forbid the exportation of the substance. A market was established for it, and every Monday, sufficient lead was sold to meet the supposed wants of the manufacturers. The prices were exceedingly high, ranging from less than ten dollars per pound up to nearly $40 per pound. The mine was never allowed to remain open more than six weeks in the year, yet the value of the yearly product is said to have reached the sum of 240,000, or much above $100,000, if we take into account the greater value of money in those days. But even the moderate working of six weeks in a year gradually diminished the supply and at last exhausted the yield, and it is now many years since any thing has been obtained from the mine except impure refuse.
Before the mine was exhausted processes were invented for cleansing and refining this refuse, which were applied to the poorer grades of the ore which had formerly been thrown aside. This purified material was then pressed into cakes, which were cut up in the same way that the natural products had been; but even this was not at all satisfactory, the pencils were of a poorer quality, in spite of all efforts.
In 1795, Centel; a Frenchman, nixed powdered clay with the plumbago or other colored powder and, by molding into the proper form, produced crayons of all shades of color and degrees of hardness. Isinglass, glue, sulphur, gum, and a hundred other ingredients had been tried, but only to result in complete failures. The new process was a complete success, and gave what could not be obtained from the native ore—a complete graduation in degrees of hardness, from the softest and blackest up to a pencil so hard that its point is like metal.
The earth or clay used has the property of diminishing in bulk and increasing in hardness in exact proportion to the length of time to which it is exposed to heat. The clay is washed until only the finest particles remain; these are mixed in the proper proportions with the plumbago and kneaded until they are thoroughly incorporated. The washing, grinding, kneading, and the proportioning of the quantities of clay to lead are in fact the most important parts of the pencil manufacture. The cake, after it comes from the machine, is put into a cylinder, and, by a blow, heavy pressure, forced out through a hole in the bottom in the shape of a square, octagonal, or round (as the case may be) continuous thread, which coils up like a rope on the board below. This is the lead for the pencils. It is then straightened, pieces cut to the proper lengths, placed close together in layers, and kept in place by a slight pressure which pre vents warping. They are then dried at a moderate temperature, and, when dry, are packed in crucibles and submitted to a high heat in ovens or furnaces. Upon the quantity of clay and length of heat are dependent the degree of blackness as well as the hardness of the product. This is the modern process, and, with one exception, is the same as that employed by Conté.
In 1846, a Frenchman, John Peter Alibert, living at that time in Asiatic Siberia, started on a business tour through the mountain regions of Eastern Siberia. Searching on his way the sandy beds of various rivers flowing into the Arctic Ocean he hoped to discover gold. No gold was found, but in the mountain gorges near Irkutsk he discovered is the sand. what was of more importance and of greater value to mankind, smooth rounded pieces of pure graphite. Immediately recognizing the importance of the discovery, he at once abandoned the search for gold and began to follow the various streams in which the graphite was found to their fountain heads in order to find the original deposit. In 1847 the deposit was found in a mountain about 170 miles west of Irkutsk, near the Chinese frontier. Men and material had to be transported through the mountain wilderness. For seven years he labored taking out granite rock and an innpure lead exactly resembling the refuse of the Cumberland mines. At the end of that time he discovered an unbroken layer of "superb graphite," from which immense pieces could be taken. He had now readied the material, the next thing was to bring it to the world. In 1856 he received the first rewards for his labor in the shape of a decoration from the Emperor of Russia. Favor was shown lnim everywhere, but it was two or three years more before the graphite from his mine made its appearance in the market in the shape of pencils, it not being until 1865 that it was introduced into this country.
We are, it will be seen, indebted to Frenchmen for the two great discoveries which have given us the moderns admirable and indispensable lead-pencil. Still later improvements in the manufacture and purifications of the best grades of lead have given the world a complete independence of any particular mine or region, and it is now asserted, and it appears pretty well substanti,ted by facts, that pencils equal to the best in the world may be made from ordinary or inferior kinds of plumbags, if the improved methods of purification and treatment be used.
The wood universally employed for pencils is red-cedar, (Juniperus Virginiania) front Florida. With its characteristics every one is acquainted, through the medium of the pencil. It is the only wood that can with profit to manufacturer or comfort to the consumer be used for pencils. It is the practice in the best manufactories in this country to cut the logs of cedar into planks the thickness of which shall be just equal to four pencils. This plank is then cut into strips of a thickness about half that of a pencil. In this conditions the wood is seasoned, and when thoroughly dry is ready for snaking into pencils. The next step is cutting into strips the length of a pencil, and, of course, four times as wide. These go to rotary cutters that groove them on one side for the leads, and on the other side snake another groove for a division between the pencils. Then the lead is dipped in glue and laid in the grooves and a plain slip of cedar fastened down upon it. The whole is then fed to a set of circular saws, which cut the pencils apart, and which, without stopping, are pushed forward to a shaping machine, where revolving cutters give them the final shape round or octagonal. Polishing is the next operation; it is accomplished by passing the pencils on an endless belt beneath vibrating surfaces covered with emery. After coloring, which is done by machinery, comes the lettering. Here the pencils are operated upon one at a time. The length of time required for all these processes, leaving out the time occupied in seasoning the wood, from the log to the finished pencil ready for the market, is about four days. This of course, is in a large establishment where machinery is employed to the greatest possible extent. The complicated machines employed in the manufacture such as we have just described, render it almost impossible to show by means of cuts the course of a pencil from its earliest stage until it is complete. We therefore present our readers with a series of cuts showing the process of snaking a pencil by bandlabor. Titans will be of still greater interest when we say that, with unimportant exceptions, the processes represented are the same as those used in the manufacture of the famous Cumberland lead.
The first process is to cut the strips of cedar or thin planks of the length of three or four pencils and width of a dozen into the proper width. This is done by a simple machine shown in Fig. 1., and a small circular saw at the same time cuts the groove for the lead, also the cover for the pencil. The next process is to fill the groove of the pencil with the lead, which is fastened in its place by glue.
The cover is then glued down, and our pencil is ready for the rounding machine shown in Fig. 2. Here a man takes one of the long sticks in each hand and places them between the small wheels shown in the cut by which they are carried to revolving cutters, which perfectly rounds the pencil as it passes through them.
They are next smoothed with a plane, and then taken by boys who, holding five or six of the sticks in their hounds at a time, pull them up and down between a leathercovered revolving roller, and a board also covered with leather. See Fig. 3. The pencils are now cut into the proper lengths by a circular sass. Another workman then takes them, places them in a block of iron which has proper holes to receive them. The ends projecting a trifle, a razor blade is then brought ,down upon them cutting tine ends off perfectly smooth. This is shown in Fig. 4.
Very often pencils have a plain stamp upon them, as well as a gilt one. This plain stamping is done by a wheel which has the required letters upon it, a grooved wheel beneath keeping the pencil in place. Fig. 5 is a representation of the machine showing the pencil as it enters. The gilt inscription on the opposite side of tine pencil is affixed by a small hand press, Fig. 6. The die in this case has the lettering arranged in a straight line, and not around a wheel. The dieholder is made hollow, so that it may be kept. hot by a red hot iron inserted in it. The gala or silver leaf is put upon the pencil in a narrow strip. The pencil is then carefully placed under the die which is brought clown lay the screw, and the type imbeds the gold or silver in the pencil.
Nothing now remains to be done but to sort the pencils, tie them up, and pack them its the form in which they reach the market.
Of the number of pencils used in a year, and of the ratio in which the different kinds are consumed, there are many interesting facts. The black round pencil seems to be the favorite, and the No. 2 is the special style. The average somber of pencils consumed in the United States in a year is estimated by good authority to be about 20,260,000. The lowest retail price would be about five cents, which would bring the commercial value at $1,013,000. The duty upon pencils of from 30 to 50 cents per gross prevents the importation of any except the finest grades. All the cheap pencils are of American make. In regard to the waste of pencils, a word should be said, namely, that only three quarters of each pencil is really used, and the remainder, or one fourth, thrown away. In effect the people of the country waste no less than $250,000 worth of pencils by throwing them away before they are used.
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