SECT. II. _Scelotyrbe festinans_: est peculiaris scelotyrbes species in qua ægri solito more dum gradi volunt currere coguntur, quod videre est apud D. Carquet, et observavit Leydæ illustr. Gaubius. _Patholog. instit._ 751, et in loquela hæc _volubilitas_ dicitur quâ lingua præcurrit mentem. Video actu mulierem sexagenariam hoc affectam morbo siccitati nervorum tribuendo; laborat enim rheumatismo sicco, seu ab acrimonia sanguinis, dolores nocte a calore recrudescunt, à thermis non sublevantur: ei præscripsi phlebotomiam, et præmissis jusculis ex lactucâ, endiviâ, et collo arietis, lene catharticum, inde vero lacticinia. Est affinitas cum scelotyrbe, chorea viti, deest flexibilitas in fibris musculorum; unde motus breves edunt, et conatu seu impetu solito majori, cum resistentiam illam superare nituntur, velut inviti festinant, ac præcipiti seu concitato passu gradiuntur. Chorea viti pueros, puellasve impuberes aggreditur; festinia vero senes, et duos tantum hactenus observare mihi contigit. Quam multos autem videmus morbos, paucissimosque observamus. De theoria et pràxi nihil habeo quod dicam; etenim sola experienta praxin cujusvis morbi determinat, et ex hac pro felici vel infausto successu theoria dein elicienda est. _Nosolog. Methodic._ Auctore, Fr. Boissier de Sauvages. Tomi. II. Part ii. p. 108.] Having made the necessary inquiries respecting these two affections, _Tremor coactum_ of Sylvius de la Boë and of Sauvages, and _Scelotyrbe festinans_ of the latter nosologist, which appear to be characteristic symptoms of this disease, it becomes necessary, in the next place, to endeavour to distinguish this disease from others which may bear a resemblance to it in some particular respects. CHAP. III. SHAKING PALSY DISTINGUISHED FROM OTHER DISEASES WITH WHICH IT MAY BE CONFOUNDED. Treating of a disease resulting from an assemblage of symptoms, some of which do not appear to have yet engaged the general notice of the profession, particular care is required whilst endeavouring to mark its diagnostic characters. It is sufficient, in general, to point out the characteristic differences which are observable between diseases in some respects resembling each other. But in this case more is required: it is necessary to show that it is a disease which does not accord with any which are marked in the systematic arrangements of nosologists; and that the name by which it is here distinguished has been hitherto vaguely applied to diseases very different from each other, as well as from that to which it is now appropriated.