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Dr. W. F. Channing had formerly experimented with camphene and other chemical burning-fluids, and he was satisfied that they do not spontaneously explode, and that they do not form an explosive mixture with atmospheric air, without the odor of the fluid becoming perceptible to the sense of smell.

Dr. J. Bigelow remarked, “that the condition of a canister having one of its apertures stopped with a porous body, was like that of a common camphene lamp with a tube and wick. An explosion would not be likely to be communicated through the porous body, nor would it take place unless some open aperture communicated with an explosive mixture within. He mentioned a remarkable case, which occurred some years ago, in the chemical laboratory of the old Medical College. The iron pipe of a stove, containing a fire, passed within a foot of a shelf on which were deposited some bottles containing different volatile oils. In the night the whole took fire, and in the morning the shelves and side of the apartment were found deeply charred, and the room filled with smoke. The fire, however, was spontaneously extinguished. On examination, it was found that a lead pipe, communicating with a water-cistern above, had been melted off, and the water had flowed down upon the fire. The bottles which contained the oil were found in their places, some broken, others with their stoppers blown out, with appearances indicating combustion rather than violent explosion."

Dr. C. T. Jackson said " he had listened to the ingenious explanation of Professor Horsford, and would take occasion to remark, that he could not conceive how a spark from pinebark tan could set fire to the vapor of burning-fluid, even allowing the spark should have passed near the slightly stoppered can. It is well known that a red-hot coal will not kindle a flame in camphene or burning-fluid vapor, and that actual flame or incandescent heat is required to inflame vapors of volatile hydro-carbonaceous fluids.

"If there was no other way to account for the combustion of the vapor from this burning-fluid, he would suggest that a

train of the vapor might have extended from the can to the stove, and have been inflamed by the fire, into which the vapor might possibly have been drawn. Dr. Jackson stated that he knew of several instances of the inflammation of ether, by flame distant from six to eight feet from the vessel containing the fluid, a train of explosive vapor, heavier than air, having formed a stratum from one end of the table to the other, and a flash having been seen to run from the lamp to the bottle of ether which was set on fire. This accident had happened in the laboratories of Dr. Hare of Philadelphia, of Mr. Hallowell of Alexandria, and in his own. Dr. Jackson did not think, however, that we knew the facts relating to the explosion of burning-fluid described by Dr. Peirson and Professor Horsford with sufficient accuracy to decide as to the true cause of the explosion in question.”

Chief Justice Shaw made the following remarks on the subject :

- I am very glad, Mr. President, to find that scientific and practical men are turning their attention to a subject which, in some of its aspects, seems to me a very important one. I was not aware that any such subject would be before the Academy this evening; but as it has been brought to your notice, if not too late, I should be glad to ask the attention of gentlemen to some of the views in which, it appears to me, it ought to be regarded.

" I do not profess to know any thing of the material character or chemical properties of this substance, nor can I pretend to say any thing respecting its mode of action, in forming gas, producing light, or causing explosion. But I feel that I am in the presence of those who are capable of applying all the science and skill necessary to a full understanding of this part of the subject, and it is to show the importance and value of these thorough and persevering investigations, that I am desirous of submitting these remarks.

“We often see an account published, headed, in attractive capitals, * Another Accident from Burning-Fluid,' and often stating a case of gross carelessness, or perhaps of pure accident, concluding with an exclamation of surprise that people will wilfully continue to use so dangerous an article.

“ This may be a very wise, or it may be a hasty and false conclusion. Gunpowder is a most dangerous article, and in the hands of the ignorant or imprudent, unacquainted with its properties and the precautions necessary to its safe keeping and use, may cause the destruction of human life; and sometimes, from unforeseen causes, not attributable to carelessness, it may unexpectedly ignite and cause great damage. Is this a reason why we should come to a hasty conclusion, that gunpowder ought never to be made and never to be used, notwithstanding its vast utility in the arts of war and peace, - supplying the most efficient arms in time of war, and acting as an indispensable agent in all the processes of quarrying and mining ? No. But it is a reason why all the causes of danger should be investigated, ascertained, and made known, and why every precaution should be taken to guard against these causes.

“ It is often suggested, I am aware, that, in using burning-fuid in preference to oil, the only object is to save a little expense in the cost, and this is an object too trifling and unimportant to warrant the running of any risk. This, it strikes me, is a very narrow and superficial view of the subject. It has been stated here this evening, that the light from camphene is whiter and purer, and the use of it more cleanly than that of oil, and the cost somewhat less. In answer to the latter fact, however, it is suggested that spermaceti oil has been much higher for a few years past than formerly, in consequence of its extensive use in manufactures. This may be the cause of a temporary rise in the price of an article, when the demand has increased faster than the supply ; and that may be especially true in regard to an article like sperm oil, when so long a time elapses between the outfit and return, and when, of course, the increase of the supply is slow in following the increase of demand. But in general, when there are no intrinsic causes to cut off or diminish the supply, the supply will, in the long run, be adequate to the demand, and then the price will be regulated by the cost of production. But it appears to me that the cause of the increased price of sperm oil lies much deeper than this. It arises from the increased length and precariousness of sperm whale voyages. I understand that voyages are greatly increased in length, and in still greater proportion in expense, from the necessity of getting supplies and repairs abroad; and the chance of falling in with the sperm whale is much rarer and more precarious ; so that vessels, after a long voyage, come home either not full, or filled with whale oil of inferior

quality. The actual cost of importation, therefore, being increased, the price at which it can be sold, must increase proportionally. If this be correct, whilst the use of artificial light is necessarily increas. ing rapidly, the resources from sperm oil are diminishing and likely to diminish still more, and the time must soon come when some other source must be resorted to, to meet this extensive and increasing want.

“But it seems to me that this is not the most important aspect of the question. There is another, affecting the labor, the industry, all the great interests of the country, more especially the great interest of agriculture, in which it deserves to be considered. Agriculture, which employs the great proportion of the entire labor of the country, which is essential to every other industrial pursuit, and forms therefore the basis of the wealth of the country, demands all the encouragement and support which the country can give it.

“Without knowing any thing in detail of the composition and chemi. cal qualities of burning-fluid, I take it for granted, - I think it has been stated here this evening, — that by far the most considerable and costly ingredient in it is alcohol or distilled spirit. Other substances may be combined with it, to fit it for its purpose of giving a brilliant light, and perhaps to check or prevent its explosive tendency, and thus guard it from danger ; of this chemists and scientific men will inform us. But distilled spirit is the substance of it.

“ If this is to be the principal, or even a very considerable, source of the artificial light of the country, it is hardly necessary to remark upon the immense quantity of alcohol which will be required. In a northern climate like ours, with a long night a part of the year, the quantity of artificial light required for manufactories, shops, stores, public buildings, and especially for domestic use, must be very large.

“ Alcohol, distilled spirit, is produced from many species of grain, -wheat, rye, oats, barley, and Indian corn. We should then produce our own material for light from our own fields, - create a home demand and a home market for the products of our own farms. It is easy to perceive what an active spring this must give, what a firm and steady support it must afford, to the agriculture of the country.

“But perhaps I may be told, that, in proportion as you use grain for distillation, you diminish the quantity appropriated for the food of the people, and render bread scarce. If it were so, it would certainly be a grave, if not a decisive, objection to this use of grain. The conconstant, full, and steady supply of grain to a country, at moderate, steady, and uniform prices, is its most important interest in an industrial point of view.

“But if I am right in my views, the argument leads to a directly con. trary conclusion; and I think it is demonstrable, that the appropriation of a considerable proportion of all the grain raised in the country to distillation, will tend to make the supply of bread more constant, regular, and uniformly cheap.

“Ours is essentially an agricultural country. There are not only very large tracts of land still unoccupied ; but the lands settled upon are not cultivated to a half, probably not a quarter, of their capacity to produce grain. This is a case, therefore, where, the source of the supply being unlimited, and the supply being able so soon to follow the demand, however large that demand may be, at remunerating prices, that supply will be met.

“ To illustrate this, taking numbers merely to designate proportions, and not absolute quantities : Supposing the ordinary demand for the purposes of food is 1,000,000 bushels of grain, and a fair remunerating price for labor and the use of land is 60 cents a bushel, then $ 600,000 would be paid the farmer for the crop. Then, supposing that by a change of habit, by which light is to be supplied from alcohol, and alcohol from grain, a demand has been established for 500,000 bushels more, and the burning-fluid distiller can afford to pay the same remu. nerating price, as the case supposes, then there will be a regular and steady demand in ordinary years for 1,500,000 bushels, and the farmer is paid $ 900,000 instead of $ 600,000 for his annual crop. The $ 300,000 a year goes steadily and regularly to the payment for labor, home labor, and the use of land.

“ This supply of grain for light, not occasional or precarious, not depending upon foreign commerce, the policy of other countries, or the contingencies of war and peace, and not depending on fancy or fashion, but being a constant, ever-recurring, and ever-increasing want for an absolute necessary of life, for which all who need it must pay a remunerating price, according to the cost of production, the demand would be as constant and steady for distillation as for consumption in bread. Indeed, the grain-market would know no difference.

" It is obviously for the interest of a country to produce annually a quantity of grain considerably beyond the average demand for consumption as food. It tends to maintain and equalize prices, and to prevent the bad effects both of short crops and superabundant harvests.

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