The most degraded savage stands infinitely above the most intelligent of the brute species by the use of two discoveries, viz., fire and artificial light. The Esquimaux, in his dreary clime, cheers his ice-tent, during his long wintry night of six months, with light from the blubber of the whale ; the Indian, in the dark tangled forest, lights up his wigwam with the blazing pine knot, or fat of the deer ; and the civilized white man illumines his houses and cities with a subtle gas made from coal obtained from the bosom of the earth, or with some of the numerous hydro-carbon fluids. Human life cannot be enjoyed without artificial light ; if man were deprived of this agent, he would become a brute. In proportion as the means of obtaining artificial light are improved, and rendered accessible to the multitude, so, in proportion, is the mass benefited and elevated in a social capacity. As the light of the sun cheers the whole world, so does artificial light increase the happiness of those who possess it. The bright fireside sends a glow of cheerfulness through the whole family circle, and the sparkling chandelier, with its numerous burners, thrills a whole assembly. How warm and cheerful, on a winter's night, is the appearance of a city whose streets are well lighted, in comparison with the dull gloom which overspreads one of our villages slumbering in darkness ! When we think of the vast extent of our artificial illumination, embracing as it does every house in the land, all the streets in our cities, and most of our villages, we must conclude that ;t forms one of the largest items of constant xpenditure belonging to communities and families. To obtain the cheapest and best artificial light, therefore, is a question of no small importance. Our intention is to present some observations on the fluids used for this purpose. Not many years ago, the only fluids employed in our country for household light were animal oils, obtained by perilous adventure on the stormy sea with monsters of the deep. At present, whale oils are in comparatively limited use for illumination, and are becoming more limited every year. Sperm oil has no superior among all the burning fluids, but it has become so dear that cheaper substitutes have been sought and obtained. The most common of these is a compound of alcohol and turpentine, commonly known by the name of burning fluid, which is very cheap and cleanly, possessing none of ttiat greasy property which belongs to oils. This fluid was first brought into public use in 1830, when a patent (now expired) was obtained for it by Isaiah Jennings, of New York City. It is composed of about nine parts of highly rectified alcohol, and one of camphene, and is capable of burning in common lamps ; were it not so volatile, no burning fluid could be more desirable. From its very nature, however, it must be used with great caution and care, because it is so liable to evaporate and become explosive by mixing with the atmosphere. Horrible accidents, causing death in many instances, have occurred from the explosion of lamps since it came into use, hence a safer substitute is desirable. From some kinds of bituminous coal a sub-spirituous oil is now manufactured, which is fast coming into popular favor, owing to the improvements which have recently been made in the means of purifying, and in the lamps designed for burning it. It is but a few years since it was first discovered that oil could be distilled at a low temperature from rich can-nelcoal, and now this oil is almost exclusively employed for lubrication in Great Britain, while it is extensively used both for lubrication and illumination among our people. Vast beds of the rich coal from which this oil can be obtained exist in Pennsylvania, Ohio and Kentucky, affording sources of supply for thousands of years to come. This oil passes over in a very crude state, incapable of being generally employed for burning on its first distillation ; but by the use of sulphuric acid, the bichromate of potash, several washings and distillations, it is purified so as to afford a most brilliant light in an argand fcwssr. Goal oils are very peculiar ; a very clear oil will come over in small quantities at a comparative low heat during distillation ; then as the temperature is raised, a greater quantity comes over, but it is thick and viscid. All these oils are liable to become red in color by exposure to the air, and they have an offensive odor. Rectified turpentine, under the name of camphene, which is very cheap, has been tried for ill imination, and judgment passed against it. It requires, like coal oil, an argand burner, and even with the greatest care it is liable to smoke, and fill up the meshes of the lampwick with resinous matter. Rosin oil, although very cheap, labors under the same disadvantages. It is a remarkable fact that while all the animal oils may be burned in common lamps, very few of the vegetable oils can be so used. The great defect of most vegetable oils for burning is their gummy nature, which causes them to clog up the meshes of the wick, and give out only a dull reddish and smoky light. The two vegetable oils capable of burning, in lamps, are made from the olive, and the seed of the brassica napus (rape seed). This oil is capable of rivaling sperm for giving a brilliant light. Patents have been taken out for purifying linseed, cotton seed, and sunflower seed oils, to adapt them for artificial light, but hitherto none of them have come into general use; the processes pursued to purify them have either been inefficient or too expensive. Neither the olive nor the rape are cultivated for oil in our country, yet the former may and ihould be, for its beautiful oil, in our southern States, and the latter for the same objects in ill our States. In France and Germany, rape seed is extensively and profitably cultivated. The oil exists ready formed in the seed and is jxtracted by pressure, like other oils obtained 'rom seeds. The seed is first ground to meal, ;hen heated to 200, placed in bags, and submitted to very severe pressure. As the oil :omes from the press, it contains some mucilage, which must be removed to fit it for burning. This is accomplished by stirring about two per cent of vitriol among it, washing with water in vats, and afterwards filtering it. The sulphuric acid unites with the mucilage of the oil, and falls down as a heavy precipitate ; the oil floats on the top of the water after standing a few days, and is then drawn off by a siphon or tap. This oil, which can be employed in common lamps, illumines the lighthouses on the French coast, which are said to be the best lighted in the world. It is, at least, an oil to which we wish to direct attention, in order to induce some of our people to introduce a useful manufacture. We are well aware that, several years ago, at the suggestion of the Lighthouse Board, a quantity of rape seed was imported, and was distributed through the Patent Office for culture ; but in our opinion, the experiments made to cultivate it were n 3t properly conducted, or else the Lighthouse Board would have been supplied with colza oil (as was their object) before the present time. As this oil is of a superior quality for lamps, neither one failure nor a number of them should discourage efforts for its development among our people.
This article was originally published with the title "Artificial Illumination—Burning Fluids" in Scientific American 13, 17, 133 (January 1858)