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inner surface of the wall B, may by radiation have varied the temperature of the outer surface A of the partition, in consequence of atmospheric changes. We should have inferred, a priori, that no variation could in this way ensue, which would be sufficiently extensive to merit consideration; and subsequently it was shown by experiments, made by Mr. Bull, in the presence of Dr. Hare, and others, that when the whole effect of the radiation from the wall B, was concentrated upon a differential thermometer, so as to be multiplied an hundred fold, it fell short of a quantity which could have produced any sensible influence upon the most sensitive mercurial thermometer.
But admitting that radiation may influence the temperature of the inner room, without proportionally altering that of the surrounding air, it cannot be supposed that a thermometer will remain indifferent to any change, thus effected. Whenever radiant caloric should be more or less rapidly abstracted from the surface A, of the partition, it would in like manner be abstracted from the bulb of a thermometer, similarly exposed. Agreeably to the plan adopted by Mr. Bull, two thermometers, one within the inner room, the other in the interval between the partition A, and wall B, were sustained uniformly at the same difference of temperature. If under these circumstances, the loss of radiant heat, could not vary without detection, to show that it might escape without altering the temperature of the air between the rooms, were a waste of time; since the measures of the operator in increasing or lessening the heat of the space intervening between A and B, were regulated by the thermometer, not by the air.
As it is notorious that many of the most useful discoveries, have been for a long time treated with neglect, the inference made by the author of the short reply, in the following passage, appears to us extremely unfair.
“ About two years ago, Mr. Marcus Bull, of Philadelphia, published a series of experiments to determine the comparative quantities of heat evolved in the combustion of the principal varieties of wood and coal used in the United States,' &c. &c. These experiments, we are told by their author, have been copied and commended in various periodical works at home and abroad ; and of course a wide circulation given to them. Their object is said to have been practical utility; and, although their length may have prevented many readers from entering into their merits, yet certain alleged facts, stated as results in a compa. rative table at the end, are intelligible to all kinds of persons; such as the fact that a cord of hickory wood, possesses more value, or more heating power, than a chaldron of Cannel, or of Liverpool coal, or than a ton of Lehigh coal; the fact that a chaldron of Newcastle coal is of less value than a cord of white oak, or of swamp whortleherry, &c. &c. with various other results equally extraordi. pary, and at variance with previous opinions on the subject.
“Two years, as has been said, have clapscd; and no great practical good is known to have grown out of Mr. Bull's experiments. The relative prices of the different kinds of fuel, continue probably the same that they would have been, if Mr. Bull had never written. Our citizens continue to pay twice as much for a chaldron of Cannel or Liverpool coal, as they will give for a cord of hickory
wood. Neither a cord of oak, nor of whortleberry bushes, can be bartered in exchange for a chaldron of Newcastle coal. Our manufacturers, whose interests are staked upon the good management of their furnaces, continue to prefer the results of their own experience, founded upon trials made in the large way dut. ing many years, rather than adopt Mr. Bull's opinions, enforced as they are by sixty pages of scientific detail.
“What then has been the cause that more practical good has not grown out of Mr. Bull's labours ? Is it that any body of men have taken the pains to pursue Mr. Bull, and to write him down in the journals and newspapers ? Is it that our manufacturers, so vigilant and discerning upon other subjects relating to their interests, are perversely blind upon this? Or is it that, after all, the cord of wood is not worth as much as the chaldron of coal; that it will not warm so many rooms, nor turn out so great a product to the manufacturer, and that Mr. Bull has been led astray in his conclusions, by fallacious experiments, and an incompetent apparatus. These are questions which the late appeal of Mr. Buli to the public, makes it proper to consider."
It is now well known, that had the labours of Fitch, in applying steam to navigation, been sufficiently patronised, he would probably have anticipated the more successful enterprise of Fullon. Yet it might have been said, with as much justice as the committee have evinced in the case of Mr. Bull, that the public continued to use stages and sail-boats, notwithstanding the efforts of Mr. Fitch to convince them of the advantages of steam.
The discovery of the absorption of oxygen by metals, was made by Rey, and confirmed by Hooke and Mayow; yet fifty years afterwards, it might have been vaunted by the disciples of Stahl, that phlogiston was not on that account the less in vogue.
At one time, it might have been alleged against Copernicus, that, in despite of his ingenious disquisitions, a majority of the learned, as well as of the ignorant, continued to consider the motion of the sun, about the earth, as an intuitive truth.
In assigning the superiority to white heart hickory, Mr. Bull clearly explained, that, in the usual mode of burning coal and wood, the advantage was greatly in favour of coal. It must then be evident, that the advice of Mr. Bull would have no tendency to induce the public to pay more for the wood, unless it should at the same time have been deemed expedient and practicable to contrive fire-places of a different construction from those now in use.
In many instances, errors endure from prejudice or ignorance, and even in opposition to the well-founded remonstrances of scientific men. After Virginia coal had been used for about twelve years as fuel for the engines at our water-works, the war, we believe, rendered a resort to wood necessary, which was then ascertained to be cheaper.
To conclude, however the remoteness of the committee from the scene of Mr. Bull's investigations, may have incapacitated them to judge of the accuracy of his manipulations, and may justify their consequent refusal to grant him a premium of great value, we cannot but consider them, on the same account, as inexcusable for detracting from the merit awarded him by prac. tical chemists, whose proximity, with one exception, afforded them better opportunities of judging. The exertions which he has made, are obviously meritorious; and, even if his deductions be as unworthy of confidence, as the committee have alleged, they may still be useful in exciting inquiry, and eliciting truth.
In page 98, Vol. ii. of the American Journal of Science, Professor Silliman says:
". This memoir, (alluding to Mr. Bull's,) is the result of a long course of ex. periments evidently conducted with great care and skill. It is replete with inieresting information, and is to be regarded as one of the most important contributions of science to the arts, and to domestic economy, which has been made for a long time in this country. It is worthy of being carefully studied both by scien. tific and practical men ; and, for the sake of the latter class, it might be well if an analysis of this practical and detailed paper, presenting in a lucid and concise form the practical and important results obtained by Mr. Bull, were prepared for publication.”
In order to lay before the reader the opinions of Professor Silliman, concerning the objections of the committee, we will subjoin his letter to Mr. Bull, page 14 of the “Defence:"
“ Yale College, July 17th, 1826. “Dear Sir,- I have twice perused with attention your communication of thre 6th instant, covering the report of the committee of the American Academy of Boston, upon the subject of your experiments upon the heat, evolved in combustion, &c.
“In reply to your request, that I would give you my opinion of the objections made by the committee, and of your reply to them, I proceed to remark:
“ 1st. I conceive that the exterior room, being sustained at a given temperature by a source independent both of the inner room and of the external air, is as good a non-conductor as can be provided, and that the inner room is as effectu. ally guarded as possible from any influence from the external air, and that it is sutficiently guarded to prevent any appreciable inaccuracy from that source.
“2d. There being no visible smoke from the anthracite coals, and scarcely any volatile combustible matter, that is not immediately consumed by the fire, there is, in the case of this fuel, no room for the combustion of the smoke ; and as the object of the experiments was to show the comparative quantity of heat evolved in the usual modes of burning fuel, in domestic economy and in the common arts, and not the whole possible amount, it did not come within your plan to compass this object, nor does it appear to be necessary for the purpose in view.
“3d. The spirit of these remarks is applicable to the third objection. Your selection of fuel appears to have been sufficiently precise to furnish the average result of the good fuel in market, and this was all that the case required.
“For my general opinions of the value of your paper, I beg leave to refer you to the American Journal, vol. ii. page 98, just published, where under the date of May 11th, you will find my impressions consisely, but fully expressed.
“ Entertaining the greatest respect for the committee of the American Academy, and having myself the honour to be a member of that body, I trust they will receive with candour the opinionis which I have expresed, and which would have been communicated with equal frankness, had I been so fortunate as to coincide with them. I remain, dear sir, your's very respectfully,
“B. SILLIMAN. “ Mr. BULL."
AMERICAN QUARTERLY REVIEW.
Art. I. — Palestine and other Poems. By the late REGINALD
HEBER, D. D., Lord Bishop of Calcutta. Now first collected. With a Memoir of his Life. Carey, Lea & Carey: Philadelphia: 1828.
It has been the complaint of the last half century, that very little of the true spirit of poetry, has preserved its existence unimpaired; and, that the prodesse volunt, aut delectare" has degenerated on the one hand, into the very questionable shape of the modern song, and the scarcely more elevated sonnet, or sunk completely on the other, into the degrading service of immorality and vice. That this complaint is in some measure true, it is the misfortune of the lovers of genuine poetry, to be compelled to acknowledge, though they will be far from disposed to receive it in that latitude of meaning in which it is generally made. There are many redeeming instances which it is unnecessary for us to stop to mention, in which the efforts of the most exalted genius have been consecrated to the service of morality and religion; and if we are not strangely mistaken, the moral taste of the age is far from deterioration.
Among the individuals, who are very far from the application of all these sweeping denunciations, stands conspicuously the prelate whose poetical effusions have been collected in the volume, the title of which is placed at the head of our present article. And so familiar has the name of Heber become, not only in the religious, but the literary circles of our country, that we feel constrained to bestow a larger share of attention on the subject, than under ordinary circumstances would be deemed advisable. If, after all, our readers should think, that we have made too large a demand on their time and patience, all the apology VOL. IV.-NO. 8.
we offer is, that every work has its extrinsic, as well as intrinsic character; and that though the present volume of Heber is small in compass, especially when compared with the great work to which our attention was lately called, yet it derives importance from the circumstances which have invested the character of its author with a deep and lively, and universal interest. Previous, however, to our entering on a critical examination of the work itself, it may be proper to make some brief general observations, touching the history of Christianity in India, in order to introduce to our readers the memoir by which the poems are accompanied, for it is no disparagement to say, that Heber, the Poet, is indebted for his greatest reputation to Heber, the ardent and devoted Bishop. To the effort to plant the religion of the Cross in the far-distant regions of the East, are we beholden not only for the “Journal” which has passed under our notice, but to much of the charm of Heber's life, and Heber's poetry.
We address ourselves to this preliminary work, confident of meeting the approbation of the great body of Christians of every name among us; and not without the expectation of furnishing some materials even for philosophic speculation. For, we believe, there are few subjects which afford greater scope for intellectual and moral investigation, than those novel phenomena of mind, which are beginning to stand out so conspicuously before the public, on the score of what is technically called “the missionary enterprise." And let the apparently feverish excitement of the age on this subject, be viewed, as some foolishly affect to view it, as a kind of epidemic mania, pervading the land, and seizing on certain persons among the high and the low, the rich and the poor ;-or let it be considered in the most favourable light, which the most zealous religionists can desire, it still affords a subject worthy of the philosopher's analysis and patient attention. But to our object.
Unquestionably, the most splendid missionary establishment which the world ever saw, was that well known under the title of the College “ de Propaganda fide.” Apart from the consideration, that one of the objects of this magnificent concern, was the aggrandizement of the Catholic church, it has challenged, and received, the admiration of the world, for the grandeur of the conception displayed in its plan,--for the truly gigantic character of its apparatus, and the prodigious energy and judgment which prepared and directed the arrangement and application of its means. Attention was early directed to the destitute and benighted regions of the East, and we have no hesitation in recording our conviction, that could a project of such extent and importance have been accomplished by human policy or power, the efforts of that society would seem to have been adequate.