The efficacy of Perkins's patent metallic tractors, in topical diseases on the human body, and animals; exemplified by 250 cases ... To which is prefixed, a preliminary discourse, in which, the fallacious attempts of Dr. Haygarth, to detract from the merits of the tractors, are detected, and fully confuted / By Benjamin Douglas Perkins.

Licence: Public Domain Mark

Credit: The efficacy of Perkins's patent metallic tractors, in topical diseases on the human body, and animals; exemplified by 250 cases ... To which is prefixed, a preliminary discourse, in which, the fallacious attempts of Dr. Haygarth, to detract from the merits of the tractors, are detected, and fully confuted / By Benjamin Douglas Perkins. Source: Wellcome Collection.