ON THE CONTAGION OF ITCH OR MANGE. 349 
of the sarcopte of these animals being taken for granted, let us 
analyse the facts of contagion attributed to them. 
Up to the present day, communication of the disease from 
the horse to man rests upon the proof of some dozen well- 
authenticated observations, half of which number might be con- 
sidered as valueless. What, indeed, are we to think of an itch 
communicated to a groom by a horse bought of a Prussian 
officer, an itch which broke out exclusively upon the chin ? and 
of the other case of veterinary surgeon Syron, who sought in 
vain, during the summer of 1808, for the acarus upon a mangy 
horse, and experienced no less, five days after, than itchy pus- 
tules upon the hands 1 The six cases exhibiting some value 
are, — 1. That by Hertwig, of a groom who looked after a 
mangy horse, and was attacked two days afterwards with a 
violent itching in the breast, face, hairy parts of the body, 
trunk, and lower extremities 2. That of a helper in the stable, 
reported by Osiander, who was in the habit of putting his cap 
upon the back of a horse that had the mange while he strapped 
him, and who contracted a scabby head difficult of cure. 3. The 
case of a countryman, related by Greve, who had ridden for a 
couple of hours a horse badly manged, during exceedingly sultry 
weather, the internal surfaces of whose thighs became covered 
with itch pustules, itching cruelly, but which, at the end of three 
weeks, disappeared without treatment. 4. That of a veterina- 
rian at Nancy, by name Mayem, who witnessed mange spreading 
rapidly to men having the care of horses, and contaminating all 
the inhabitants of a village without distinction of age or sex. He 
communicated this extraordinary fact to the Academy of Dijon, 
of which he was a member. 5. The case, not less remarkable, 
published by ich, who knew two hundred horsemen catch the 
itch from their manged horses. Inflammator}' swellings made 
their appearance on their faces, as well as their arms and 
thighs ; these parts became covered with dense black incrusta- 
tions, and, in most of them, the face swelled to that degree that 
the eyelids could hardly be opened. 6. Lastly, the case re- 
ported by Professor Vibeng, of Copenhagen, of horses who 
repeatedly affected the men who looked after them. 
Such are the most demonstrative facts of the transmissibility 
of itch from horse to man : others might be adduced, but they 
lack the proof of the presence of the insect. 
The transmission of the itch from the goat to man rests upon 
the authority of LouisFranck*, Strauss-Durkheimt,M.HamentJ, 
• Collection d’Opuscules de M£d. Pratiq. avec un Memoir sur le Commerce 
des N^gres au Cairo. 
f Cited by Hering. 
X L’Egypte sous Mehemet Ali. 
VOL. XXIV. 3 B 
