ACETYLENE GAS LAMPS.
Although nearly two years have elapsed since the introduction of acetylene for purposes of general illumination, yet the present season is the first one in which this new illuminant has been used in bicycle lamps, and it seems eminently fit and proper that this gas should be appropriated to the uses of wheelmen, because it was in 1888, at Spray, N. C., that Mr. Thomas L. Willson, a member of the Kings County Wheelmen of Brooklyn, N. Y., who was famous in his day as a hardy road rider of the old “[ordinary]” and presented to his club the trophy that bears his name, while experimenting on the reduction of refractory metallic oxides of carbon in an electric furnace came upon the happy but unexpected outcome of producing by a cheap and simple method calcium carbide, so that the use of acetylene became at once a commercial possibility. He was trying to obtain the metal calcium by reducing lime with pulverized charcoal, but the temperature of the arc fused the mass, and it solidified into an extremely hard, gray crystalline rock. As this was not the substance that Willson sought to produce, it was thrown into a stream near by, and there was an instant evolution of gas in large quantities which, when lighted, burned with a smoky, luminous flare. Chemical analysis showed the rock to be carbide of calcium (Ca C) containing 60 parts by weight of calcium and 40 parts of carbon, and its gaseous offspring to be acetylene. This generation of acetylene by means of the immersion of carbide of calcium in water is the result of two exceedingly simple chemical reactions. The carbon in the carbide unites with the hydrogen in the water to form acetylene, and the calcium in the carbide takes up the oxygen of the water to form slaked lime, the only by-product of the double reaction.
Acetylene is a gaseous compound of 24 parts by weight of carbon and two of hydrogen. Although it was first discovered and isolated by Davy in 1836, it was twenty-three years later before the scientific world obtained a clear conception of its interesting character and properties through the investigations of M. Berthelot. Since that time, and up to the discovery as before stated by Mr. Willson, it had been produced only in small quantities as a laboratory product by tedious and costly processes.
Acetylene, when burning, gives a flame of intense brilliancy, and owing to its richness it can only be consumed in small burners. It possesses not only great luminosity, but great diffusive qualities. The light produced by acetylene is of a pure white color, soft and agreeable in tone. It resembles sunlight more closely than any other known luminant. Pure acetylene is not explosive. Mixed with air in certain proportions it can be detonated, and the same can be said of every known gas; but in a bicycle lamp, containing an ounce and a half, or two ounces at the utmost, of the calcium carbide, there cannot be produced enough gas to cause an explosion.
KLONDIKE
(KEROSENE).
Calcium carbide is a hard, porous, grayish-black or bluish-gray incombustible material somewhat crystalline in form, odorless and unchangeable in a dry atmosphere, but when subjected to moisture gives off more or less acetylene gas. Carbide cannot be ignited and when well packed to prevent its coming in contact with water it is safe as regards all the conditions of transit and storage. When a piece of carbide is exposed to the moisture of the air a slight decomposition on the surface of the lump causes the formation of a thin layer of lime dust, which retards further deterioration.
THE “SOLAR”
(ACETYLENE).
Interior View.
Its combustion is perfect. There are no noxious products, no odor, and no smoke. The vitiation of the air in a room compared with the ordinary gas is as 1 to 8. It produces a distinctively cool flame. The same amount of light has only one-sixth the heat of city gas. Its cost is far less than that of any known illuminant. It is made of cheap and almost universal materials, coal and lime, fused by electric heat. It will be in this respect the light of the masses. It will not freeze, being unaffected by heat or cold. It can be cooled to 100 degrees below zero, or heated to 600 above, without impairing its illuminating power.
If through ignorance or accident an acetylene gas jet should be blown out or the burner left open, the gas, being rather irritating, can be easily detected, even in the smallest quantities, on account of its penetrating odor, which resembles that of garlic. So pungent is this odor that it would be practically impossible to go into a room which contained any quantity of acetylene gas.
The carbide group is by no means unfamiliar to the average man; cast iron and steel are iron carbides of a peculiar form, and not a few others are daily used, for instance, Harveyized armor plates. They are all characterized by an almost adamantine hardness, and at the same time a certain instability. This instability reaches its maximum in the group of substances which are capable of making what chemists call hydroxides. They are all unions of a base with carbon, made in the electric furnace, and all give off gases when brought in contact with water. When broken into pieces suitable for shipment the carbide is packed in cans, the space between filled with sawdust, or some such substance to prevent waste by the rubbing of piece against piece, and the can sealed airtight to protect its contents from the moisture of the atmosphere. This is the shape in which it comes to the consumer. On opening the can one often finds most beautiful crystalline structures on the fractured surfaces, but they are instantly attacked by the dampness of the air, and one sees the beauty give way to a dirty gray powder with a feeling of disappointment which is very real.
Very little has been written about acetylene gas, and very few wheelmen have had any experience with acetylene gas lamps on their bicycles. The writers, however, have thoroughly investigated the subject of producing the carbide and the gas, and have for some time past had in daily use two of the lamps mentioned in this article, namely the “[Electro]” and the “[Calcium King].” They have been used, of course, with the usual care that it is necessary to use with any bicycle lamp, whether it uses oil, electricity or gas, and the results have been satisfactory in every way, and the lamps have done all that the makers claim for them. This mention has been made to show that what has been written here concerning acetylene gas and portable bicycle lamps is founded upon scientific data, and it is, therefore, not wholly an empirical result.