BIOLOGICAL EXPERIMENTS. 241 



are connected with the instrument. Have we not here a clue to 

 the extraordinarily contagious character of the excitement arising 

 amongst persons whose emotions have, in any way, been wrought 

 upon, especially those in whom the highest brain-centres have not 

 been well developed ? The " Dancing Manias " of the middle 

 ages form a case in point. The contagion (if I may be allowed 

 the expression) spread from town to town, just as the advance of 

 a disease like cholera may be noted step by step. The first 

 authentic records of the dancing mania occurred in 1374, and in 

 that year large assemblages of men and women appeared in 

 Aix-la-Chapelle, and, taking hold of each ofhe?''s hands, seemed to 

 have lost all control over their senses. They continued dancing 

 for hours together in wild delirium, until they fell to the ground 

 in a state of exhaustion.* Their sufferings were relieved, as in the 

 case of the convulsionnaires, at St. Medard, many centuries after, 

 by sound beatings and tramplings upon the most sensitive parts of 

 the body. When the disease was further advanced, the attacks 

 commenced with epileptic convulsions. 



In a few months this extraordinary malady spread from Aix-la- 

 Chapelle to Cologne, and from thence into the Netherlands. In 

 Metz, as many as eleven hundred, and in Cologne five hundred 

 dancers filled the streets. Peasants left their ploughs, mechanics 

 their workshops, housewives their domestic duties to join the wild 

 revels, with such consequences, both to commercial prosperity and 

 morality, as may readily be imagined. The disease waxed and 

 waned, but did not completely die out till the i6th century. The 

 exciting cause, so far as it can be traced, seems to have been the 

 terror and despair felt by the inhabitants of Europe at the frightful 

 ravages caused by the Black Death and the Plague. 



Strange, contagious, nervous disorders have also been very 

 frequent in convents, where a number of under-educated women 

 are living together under conditions in which all healthy emotions 

 are killed out, or placed under cruel restraints, and all unhealthy, 

 hysterical emotions are fostered. In a well-known case, one nun 

 in a convent having begun to mew like a cat, all the other nuns 

 began to mew also, and nothing could put an end to this odd 

 chorus, until a company of soldiers were placed before the doors 

 * " The Dancing Mania of the Middle Ages." F. F. C. Hecker, M.D. 



