Subsistence. Those public Works, therefore, such as Roads, Canals, &c., by which Fuel may be brought cheap into such Countries from distant Places, are of great Utility; and those who promote them may be reckoned among the Benefactors of Mankind. I have great Pleasure in having thus comply'd with your Request, and in the Reflection, that the Friendship you honour me with, and in which I have ever been so happy, has continued so many Years without the smallest Interruption. Our Distance from each other is now augmented, and Nature must soon put an End to the possibility of my continuing our Correspondence; but, if Consciousness and Memory remain in a future State, my Esteem and Respect for you, my dear Friend, will be everlasting. B. FRANKLIN. Notes to the Letter upon Chimneys No. I The latest work on architecture, that I have seen, is that entitled Nutshells, which appears to be written by a very ingenious man, and contains a table of the proportions of the openings of chimneys; but they relate solely to the proportions he gives his rooms, without the smallest regard to the funnels. And he remarks, respecting those proportions, that they are similar to the harmonic divisions of a monochord. He does not indeed lay much stress on this; but it 1 "It may be just remarked here, that upon comparing these proportions with those arising from the common divisions of the monochord, it happens, that the first answers to unisons; and, although the second is a discord, the third answers to the third minor, the fourth to the third major, the fifth to the fourth, the sixth to the fifth, and the seventh to the octave." - Nutshells, page 85.- ED. shows that we like the appearance of principles; and where we have not true ones, we have some satisfaction in producing such as are imaginary. No. II The description of the sliding plates here promised, and which have been since brought into use under various names, with some immaterial changes, is contained in a former letter to James Bowdoin. 1599. DESCRIPTION OF A NEW STOVE FOR BURNING OF PITCOAL, AND ALL ITS SMOKE.1 CONSUMING TOWARDS the end of the last century an ingenious French philosopher, whose name I am sorry I cannot recollect, exhibited an experiment to show that very offensive things might be burnt in the middle of a chamber, such as woollen rags, feathers, &c., without creating the least smoke or smell. The machine in which the experiment was made, if I remember right, was of this form, (Plate XV. Fig. 1,) made of plate iron. Some clear burning charcoals were put into the opening of the short tube A, and supported there by the grate B. The air, as soon as the tubes grew warm, would ascend in the longer leg C and go out at D, consequently air must enter at A descending to B. In this course it must be heated by the burning coals through which it passed, and rise more forcibly in the longer tube, in propor 1 From Transactions of The American Philosophical Society (Old Series) II: : 57. It was read at a meeting of the Society, January 28, 1786. — Ed. Subsistence. Those public Works, therefore, such as Roads, Canals, &c., by which Fuel may be brought cheap into such Countries from distant Places, are of great Utility; and those who promote them may be reckoned among the Benefactors of Mankind. I have great Pleasure in having thus comply'd with your Request, and in the Reflection, that the Friendship you honour me with, and in which I have ever been so happy, has continued so many Years without the smallest Interruption. Our Distance from each other is now augmented, and Nature must soon put an End to the possibility of my continuing our Correspondence; but, if Consciousness and Memory remain in a future State, my Esteem and Respect for you, my dear Friend, will be everlasting. B. FRANKLIN. Notes to the Letter upon Chimneys No. I The latest work on architecture, that I have seen, is that entitled Nutshells, which appears to be written by a very ingenious man, and contains a table of the proportions of the openings of chimneys; but they relate solely to the proportions he gives his rooms, without the smallest regard to the funnels. And he remarks, respecting those proportions, that they are similar to the harmonic divisions of a monochord.' He does not indeed lay much stress on this; but it 1 "It may be just remarked here, that upon comparing these proportions with those arising from the common divisions of the monochord, it happens, that the first answers to unisons; and, although the second is a discord, the third answers to the third minor, the fourth to the third major, the fifth to the fourth, the sixth to the fifth, and the seventh to the octave." - Nutshells, page 85.- ED. shows that we like the appearance of principles; and where we have not true ones, we have some satisfaction in producing such as are imaginary. No. II The description of the sliding plates here promised, and which have been since brought into use under various names, with some immaterial changes, is contained in a former letter to James Bowdoin. DESCRIPTION OF A NEW STOVE FOR BURNING OF PITCOAL, AND ALL ITS SMOKE.1 CONSUMING TOWARDS the end of the last century an ingenious French philosopher, whose name I am sorry I cannot recollect, exhibited an experiment to show that very offensive things might be burnt in the middle of a chamber, such as woollen rags, feathers, &c., without creating the least smoke or smell. The machine in which the experiment was made, if I remember right, was of this form, (Plate XV. Fig. 1,) made of plate iron. Some clear burning charcoals were put into the opening of the short tube A, and supported there by the grate B. The air, as soon as the tubes grew warm, would ascend in the longer leg C and go out at D, consequently air must enter at A descending to B. In this course it must be heated by the burning coals through which it passed, and rise more forcibly in the longer tube, in propor 1 From Transactions of The American Philosophical Society (Old Series) II: 57. It was read at a meeting of the Society, January 28, 1786. — Ed. For such a machine is a and off ved syphon; a de gaz va fi bir kg of a was good a descending is accompanied by an ascent of the une fud in the sorment st. in this invented syphon, * greater quantity of levity of air in the longer leg, in rising ʼn wompanied by the descent of air in the shorter. The i sking to be bored being laid on the bot coals at A, the vandike must descend through those coals, and be converted into fame, which, after destroying the offensive smell, came olt at the end of the longer tube as mere heated air. Whoever would repeat this experiment with success, must take care that the part A B, of the short tube, be quite full of burning coals, so that no part of the smoke may descend and pass by them without going through them, and being converted into flame; and that the longer tube be so heated as that the current of ascending hot air is established in it before the things to be burnt are laid on the coals; otherwise there will be a disappointment. It does not appear, either in the Memoirs of the Academy of Sciences, or Philosophical Transactions of the English Royal Society, that any improvement was ever made of this ingenious experiment, by applying it to uesful purposes. But there is a German book, entitled Vulcanus Famulans, by John George Leutmann, P. D., printed at Wirtemberg, in 1723, which describes, among a great variety of other stoves for warming rooms, one, which seems to have been formed on the same principle, and probably from the hint thereby given, though the French experiment is not mentioned. This book being scarce, I have translated the chapter describing the stove, viz. |