M New Use for Cotton By Frank N. Bauskett R. HARVIE JORDAN, President of the Southern Cotton Association, declares that the manufacture of paper from fiber of the cotton stalk is one of the latest and most interesting inventions of the new century. For many years expert inventors have been busily engaged experimenting with the cotton. stalk, and recent developments give assurance that their labors are to be rewarded with signal success. "It has been unquestionably demonstrated," declared Mr. Jordan, " that all grades of paper, from the best form of linen grade to the lowest, can be manufactured from cotton stalks. In addition to this, a variety of by-products, such as alcohol, nitrogen, material for guncotton and smokeless powder, can also be secured in paying quantities. The time is not far distant when paper plants equipped with all modern machinery and devices for making paper and for the utilization of the other byproducts referred to, will be built and placed in operation throughout the cotton-growing States of the South. The establishment of these mills for the manufacture of paper from cotton stalks will at once develop a new industry of quite enormous proportions, and institute the utilization of a waste product which at the present time has comparatively little or no value. It will prove the entering wedge of checking the present increasing cost of paper, which is becoming such a burden upon the newspaper industry of the country." It is estimated that on an area of land producing a bale of cotton, at least one ton of stalks can be gathered. Upon this basis of calculation, this new industry can annually depend upon from 10,000,000 to 12,000,000 tons of raw material. This will not only furnish necessary supplies to meet all home demands, but also permit of the export of pulp or finished products to foreign countries. At the present time there is approximately $287,000,000 invested in paper mills in the United States, with but few plants located in the South. The bulk of the material going into the manufacture of paper at the present time is spruce, which is annually becoming more expensive, owing to depletion of the forests and the high prices which such timber commands in the market for other purposes. The practical effect of this new invention will be to increase the present value of the cotton crop of the South by nearly $100,000,000 annually. The growers will be amply paid for the expense of removing the stalks from their fields and of delivery to the paper plants, and will in addition receive a substantial profit on this product of their labor. With the removal of the cotton stalks from the fields in the early fall, the death knell of the boll weevil will be sounded and its present work of devastation stopped. Paper manufactured from the cotton stalk is of the strongest texture and softest finish. Several plants will be erected during the next few months in the South, which will be in full operation by the first of next year. Are you worried by any question in Engineering or the Mechanic Arts? Put the question into writing and mail it to the Consulting Department, TECHNICAL WORLD MAGAZINE. We have made arrangements to have all such questions answered by a staff of consulting engineers and other experts whose services have been specially enlisted for that purpose. If the question asked is of general interest, the answer will be published in the magazine. If of only personal interest, the answer will be sent by mail, provided a stamped and addressed envelope is enclosed with the question. Requests for information as to where desired articles can be purchased, will also be cheerfully answered. Tarring Fence-Posts Is coal-tar of value in prolonging the life of fence-posts?-A. O. T. A coating of tar applied to that part of the post which is buried in the ground adds considerably to the durability of the wood. The tar protects against moisture and other deleterious influences that rot the wood. While it is not at all necessary that the tar should be laid on lavishly, yet enough should be used to give a coating that will thoroughly penetrate the grain. Cleaning a Lens Scratched lenses on my camera convince me I am not cleaning them in the right way. Please advise me in this matter.-E. R. S. Lenses, as a rule, receive too much rather than too little attention, and unfortunately this attention is of the wrong kind. Dust and grease alone are the kinds of dirt that need to be removed. This is too often done by rubbing the surface of the lens with any cloth or rag that may happen to be conveniently near. On the other hand, it is not necessary to use chamois skin, which indeed is likely very soon to become impregnated in its turn with dust and grime. The best cleanser is an old handkerchief of soft texture that has been thoroughly washed to remove all foreign particles. This Refrigerator without Ice Is there such a thing as an iceless refrigerator?-E. S. L. What is called an "iceless refrigerator" has recently been put on the market. It is simply an ordinary ice-box, not insulated, and covered with a porous material. Overhead is placed a pan of water which is fitted with an automatic device for periodic discharge of the water, in order that the porous blanket may be remoistened. From this brief description, one can readily see that the principle of evaporation is called into use to maintain a low temperature. The old Indian method of suspending a jar of water in a wet blanket is merely repeated in another form. On days when the hot winds. blow, this system of refrigeration will work well; but when the atmosphere is charged with moisture and no breeze is stirring, the iceless device will be of little practical value. To Pierce Hard Metal Please explain how to drill a hole in very hard metal.-A. V. Good tools are requisite for drilling in hard metals. A well-hardened drill only should be employed. Have an abundant supply of oil, and' drive the drill slowly but with as much force as the point will bear. To harden the drill, heat to a dull glow in a charcoal flame, and cool in mercury. The work will be further facilitated if the surface of the metal to be pierced is first nicked with a cold chisel. Chilled cast iron may be softened by putting sulphur on the place to be penetrated, and then heating the iron to a glow. Cracks in Concrete Wall Why is it that a concrete wall in which iron posts are set is sometimes cracked around the posts?-H. T. The concrete may not have been properly prepared, or it may have dried too quickly; perhaps, too, expansion joints were omitted. The wall, when newly laid, should be cut every 45 or 50 inches. These cracks should at once be filled with dry sand of a fine grain. The joints. or cracks allow for the contraction or expansion of the concrete, which accompanies every change of temperature. The Nernst Lamp They have recently installed Nernst lamps in some of the stores in our town. Will you please explain this form of light and how it operates?-F. J. S. The Nernst lamp is a form of incandescent lamp, using for the incandescent material certain oxides of the rare earths. The oxide is mixed in the form of a paste, then pressed through a small orifice into a string, which is subjected to a roasting process, forming the filament or glower material of the lamp. The glowers are cut the desired length and platinum terminals attached. As the glower is a non-conductor when cold, some form of heater is necessary to bring it up to a temperature at which it will conduct. One form of heater is made of fine platinum wire wound upon a porcelain tube as a support and covered with porcelain paste. The heater tubes are mounted just above the glowers in the finished lamp. The heating device is connected. across the circuit when the lamp is first turned on, and must be cut out of circuit automatically when the glower becomes a conductor. This automatic cut-out is operated by means of an electro-magnet so arranged that current flows through its coil as soon as the glower conducts, and opens a form of silver contact, cutting out the heater. The conductivity of the glower increases with its temperature; hence, if used on a constant-poten tial circuit, its temperature would continue to increase, because of the greater current flowing, until the glower was destroyed. To prevent this increase of current, a ballast resistance of fine iron wire is connected in series with the glower. The resistance of the iron wire increases rapidly with increase of tem 6 3 TYPICAL DIAGRAM OF NERNST LAMP CIRCUIT. perature, and thus prevents the increase. of current through the glowers. The accompanying figure shows complete connections for a 6-glower lamp. The current enters, say, at terminal 1, passes through the contacts of the cutout 4, to the heater circuit 5, then to contacts 4' and to the terminal 2. When the glowers become hot enough to conduct, the current divides at 1', part of it passing through the glowers 6, the ballast 7, and the cut-out 3, to terminal 2. When the current in the glowers has reached its normal value, the contacts at 4 and 4' open, cutting out the heater coils entirely. Making a Thermopile How is a thermopile constructed and used? -F. H. N. The thermopile is an instrument used in the production of such small, steady currents as are required for grading delicate ammeters and voltmeters. In conjunction with the galvanometer, it is also useful for registering minute variations. of temperature in furnaces, where no ordinary thermometer could stand the melting power of the intense heat. In construction, the thermopile consists of one or more paired pieces of dissimilar metals. These metals are in the form of wires or blocks and are joined together at one end. Antimony and bis The wires should then be placed in a vise, with the ends projecting so that they may be twisted together with a pair of forceps. The twist is next soldered together. To prevent rusting, resin rather than the customary acid or soldering fluid is the best available material. The free end of the wires should now be drawn apart, so as to leave a space of some four inches between the extremities, as shown in the figure (a,b). These extremities are next connected to the terminals of a delicate galvanometer. If the galvanometer's pointer is then brought to 0°, on applying fire to the junction c, a current strong enough to deflect the pointer through 10° or 15° will be set up. A dozen combinations of this kind will increase the power of the arrangement. In such case, vires of a length of four inches should be used. A twist of threefourths inch will suffice. Tightening Steam Joints-Lime in Pipes 1: How can steam joints be made tight? 2: How can lime be removed from injectors and delivery pipes?-A. G. R. 1: First, take white lead ground in oil; incorporate as much black oxide (manganese) as possible; and add a small portion of litharge. Knead it with the hand, dusting the board with red lead. Make the mass into a small roll, and put the roll on the plate after having first oiled with linseed oil. It can then be smoothed and pressed into position. 2: Mix 1 part muriatic acid to 10 parts of soft water, and let the tube remain in the mixture over night. THERMOPILE. muth have been more frequently employed than other metals. In some respects, however, copper and nickel are. more satisfactory. These metals should first be cleaned with fine emery paper. Use of Loam Mould Under what conditions should a loam mould be used?-P. O. D. Where the casting is large, and it would be too expensive to provide a pattern, loam moulds are employed. The casting, however, must be of a quite simple form, otherwise a pattern will be essential. Good results may be obtained by using a partial pattern with the loam mould. The basis of the mould is brick, over which the loam is spread. |