‘One of the best kinds of cement for resisting the action of fire I ever met with was composed of equal parts of brick dust, quick lime, and iron filings, mixed up with blood. It unites itself firmly to metals as to bricks and stones of all kinds, and even the most intense fire seems to have very little effect on it. It may even be made to join metals to stones, or even wood to metals. Our soap boilers in Bavaria use it to join the wooden tops of their boilers to their copper bottoms, which it does in so effectual a manner that they are very seldom found to leak. It was from them I learnt the secret of the composition of this most useful cement. I have no doubt but it would be found to answer very well for plastering the backs and covings of open chimney fire-places. I wish you would make a trial. If it should be found to answer it would be a most important discovery, for in that case bricks would certainly be as good, or even better, than fire-stones for constructing fire-places. ‘I am, dear Sir, with unfeigned regard and esteem, ‘Yours most faithfully, ‘RUMFORD.’ _From the Duke of Grafton_ ‘Piccadilly: 1799. ‘Dear Sir,—I had but just time to cast an eye on Mr. Wilberforce’s letter last night, and seeing that the references are so many to texts of Scripture, I must desire you to leave it with me till I can have a good hour’s leisure to give it that consideration which everything from him must deserve. ‘I wish Mr. Wilberforce[192] and myself were agreed upon all points as we are on the (I fear) hopeless attempts to abolish totally the slave trade. Depend upon it that no one who knows that gentleman so little honours him more than myself; nor do I impute any opinions or dogmas to him which I have not learnt from his writings. I believe him to be an upright, sincerely pious and beneficent character, treading a road that leads to future happiness, even should he be under great but involuntary errors. Will he say the same of any one of those whom he improperly calls Socinians? For, though they honour the memory of Socinus, they do not follow his faith; far from it, for they acknowledge no masters on matters of religion but Christ and His Apostles. ‘Yours very faithfully, ‘GRAFTON.’ _From Dr. Burney_[193] ‘Dover: Sept. 11, 1799.