Your letter of Jan. 27. was, by some accident, very long on the road & I have been tardier in acknoleging the reciept of it, because I really needed no confirmation of what you had written me yourself on your improvement of fireplaces. I know that in the best I have yet seen, a great proportion of the heat is carried off without having entered the apartment; and there being so much room for economising this by new inventions, I readily believe in those stated to me by persons whose words I have no reason to question. I am the later in writing too, because I could recollect no acquaintance whose turn of mind lay that way & whom, according to your desire, I could ask to call on you for more particular explanations than you had given me by letter. it now occurs to me that mr Fulton may be at N. York or may pass that way, and I write him a line to ask the favor of him to call on you, examine your fire place and give me his opinion on it. and this is done merely because you ask it, and not because I doubt. your former explanation of it, altho’ considerably detailed, has not given me a sufficient understanding of it. perhaps this could be done by some rough drawing which might come by post, as competently as by a model, which however small & of wood, could not come but under the care of some passenger in the stage coming to Richmond. besides, I could offer you no advantage equivalent to all this trouble, being retired too far inland to have effect in recommending their use. if I should once understand it, I should be disposed to endeavor to get one to use in my own cabinet, as soon as the sea should be open for it’s safe passage, and perhaps I might induce some of my friends in Richmond to introduce them there. a fire made with one tenth of the ordinary fuel, & kept up but one hour in five offers advantage & comfort enough to try the experiment. wishing you the best success in this improvement I pray you to be assured of my respect.

Th: Jefferson