(1801-1867) American Quaker doctor and ardent abolitionist, President of the Pennsylvania Anti-Slavery Society. Uncommon A.L.S. ‘Caspar Wistar’ 2pp. 4to., Philadelphia, Feb. 15, 1844, to Doctor Harris, in part: ‘…Although personally unknown to each other, I take the liberty of addressing thee as a member of the same profession. The death of two children within a short time, and the sickness of several others at Yardley Warner’s School to which I understand thou art the medical advisor, has filled my mind of the parents & friends of the pupils with no inconsiderable apprehension lest some local cause may be operating injuriously on the health of the children placed in that Seminary; and I have again and again been applied for an opine on the subject. I must confess my own fears have been somewhat awakened…to my own child who is at present an inmate of the School…I shall therefore much obliged by thy opinion on the matter as I presume thou art familiar with the character of that…County and whether there can be any local circumstances as an epidemic of influenza…’. Boldly penned, very good, and worthy of further research.