Marat evidently had in mind other medical works. In the Essay on Gleets[5] he says, “If this essay should meet with approbation, I shall offer to the public a new method of radically curing gonorrhœas in a short time.” And again, in the tract on Diseases of the Eye,[6] speaking of the action of mercury, “A complete Examination of them would swell these Sheets beyond the proposed Size; I therefore reserve it for the Subject of a future Publication.” It may, I think, be safely said that these intentions were never carried out. Watt, in his _Bibliotheca Britannica_, gives the titles of the two tracts here reprinted, but makes no mention of the others; and, so far as I can find, they never saw the light. The _Daran_ under whose care the cases described in the first tract were before they came under Marat’s observation, was Jacques Daran [1701-1784], a man who greatly distinguished himself whilst in the army during an epidemic of the Plague at Messina: after travelling all over Europe he lived at Marseilles, but finally settled in Paris. He was chiefly celebrated for his bougies for the treatment of diseases of the urethra: the composition of the bougie he kept a secret, and thus amassed a very large fortune. He ultimately, however, died at Paris in very poor circumstances. The famous _T_***, under whose care the case described on page 17 was, I cannot identify with any degree of certainty. The “ingenious Mr. _Miller_, Oculist,” mentioned on page 44, was probably John Miller, an optician, who died at Edinburgh in 1815, having occupied for forty-eight years a leading position in that city. He was originally in business at 7 Parliament Close, and afterwards was in company as Miller and Adie in Nicolson Street. The original tracts are printed in 4to without any running title; the top of each page simply having the pagination in square brackets. The reprints follow the originals exactly as regards orthography, punctuation, etc. Obvious errors have not been corrected: the pamphlets are reproduced exactly as Marat wrote them. Marat’s nationality comes out very strongly in more than one passage, where, whilst using English words, he has kept entirely to the French idiom. In the preface to the first tract he apologises for his imperfect knowledge of the language in which he is writing. The tract on the Eye is printed with that prodigality of capitals so common in books of that date: curiously enough the one on Gleets is entirely free from this lavish use of capitals, and only has them where absolutely necessary. There is no note (_b_) in the original of the “Eye” tract: the letters have been followed exactly.