Trousseau later introduced an element of precision into current therapeutic measures by the application of a sort of gymnastic exercise to the muscles involved. He declared his opinion, however, that the arrest of one tic would soon be followed by the development of a second, which would in turn give place to a third, and so on; for the disease was essentially chronic, and in a sense formed part of the constitution of its subject. Subsequent observation has frequently borne witness to the truth of this remark, though the expression is too absolute. For the majority of the older writers, nevertheless, the incurability of tic was axiomatic. Pujol held non-dolorous facial tic to be most intractable. In the hands of Duchenne of Boulogne faradisation of the muscles was followed by only transient improvement. Axenfeld considered idiopathic facial convulsions hopeless from the point of view of treatment. It has been remarked already that many of the earlier observers failed to discriminate between tic and spasm. In the article "Face" in the Encyclopædic Dictionary, for instance, Troisier includes every sort of facial movement under the term "convulsive tic," among them reflex spasms from dental caries or buccal ulceration, and muscular contractions occasioned by peripheral or nuclear irritation. His opinions as to the curability or otherwise of these movements are sufficiently dogmatic: "Convulsive tic is not a serious condition, yet it is in a majority of cases incurable and as a consequence most distressing. One can hope for success only if the tic is of reflex origin, where extraction of a tooth, or local treatment of an ulcer, or resection of part of the trigeminal nerve may be indicated." Here the confusion is obvious. Gilles de la Tourette's description of the disease known as convulsive tic accompanied with echolalia and coprolalia is couched in equally pessimistic terms. "It is no menace to existence, and the patient may well attain a ripe old age, but in revenge he stands very little chance of escaping from it. A radical cure is yet to be found. Isolation, hydrotherapeutics, electricity, and constitutional treatment cannot do much more than retard its evolution." In Guinon's article on convulsive tic in the Encyclopædic Dictionary of the Medical Sciences of 1887 thirty pages were devoted to description and the following few lines to treatment: "This chapter will of necessity be brief.... In presence of this affection the physician is unfortunately helpless. During exacerbations any nerve sedative may be tried. In severe cases or if the symptoms become aggravated, the sole treatment likely to be accompanied by improvement, scarcely by success, is a combination of hydrotherapeutics with isolation." Nor is Charcot much more encouraging[194]: