Letter : on ventilation, &c. written by Mr. Small, the surgeon, but containing Dr. Franklin's observations on the subject. From: Memoirs of the life and writings of Benjamin Franklin ... / written by himself to a late period; and continued to the time of his death by the grandson, William Temple Franklin; comprising the private correspondence and public negociations [sic] of Dr. Franklin and his select political, philosophical, and miscellaneous works, published from the original mss. Second edition. London: Printed for Henry Colburn, 1818-1819.

Dr. Small describes his own and Benjamin Franklin's concerns about inadequate ventilation of houses, hospitals, and other public buildings. Examples of poorly ventilated structures leading to disease, and of ways to provide ventilation (especially through existing chimneys) are provided. The second part describes the noxious health effects of sewage, with examples of the benefits of proper sewers and of properly constructed drainage systems.