rheumatism do rarely occur in which a very high temperature is not accompanied by cerebral disturbances. Sibson quotes two such,[97] one of which, with a temperature of 110.8°, was only restless and talked when asleep, and the other, with a temperature of 106.3°, presented only vomiting and dyspnoea. Cardiac inflammation was absent in both. DaCosta relates one in his valuable paper upon cerebral rheumatism in which, although the temperature was 110°, no cerebral symptoms nor cardiac affection existed.[98] [Footnote 96: "Abstract Report upon Hyperpyrexia in Ac. Rheum.," _Brit. Med. Jour._, 1882, p. 807.] [Footnote 97: _Lib. cit._, p. 264.] [Footnote 98: This essay contains a record of 11 cases of cerebral rheumatism and several autopsies: _Am. Jour. Med. Sci._, 69, 1845, p. 36, case xi.] The goodly number of instances lately published in which grave cerebral symptoms have obtained in acute articular rheumatism at ordinary febrile temperatures, while they prove that hyperthermia is not an essential condition productive of such symptoms, require to be explained. Some such, no doubt, have been instances of marked predisposition, so that a moderate febrile temperature or some complication sufficed to disturb the brain, as we see in typhoid and other fevers, in pneumonia, etc. If there be a rheumatic poison--which has not yet been proved--it may, in predisposed persons, produce the cerebral symptoms. The argument[99] that such poison should produce inflammation of the nervous centres if it acted directly on them is not convincing. It need not necessarily produce similar alterations in serous or synovial membranes and in nervous tissues. Many toxic agents disturb, and even suspend, the {42} cerebro-spinal functions, and leave no appreciable changes in them. Do these cases prove that there is something peculiar to rheumatic fever which tends to disturb the nervous centres? Hardly; for while such disturbance is comparatively rare in that disease, it is observed frequently in many other febrile affections, notably in typhus, scarlatina, and small-pox; and as in these, so in rheumatic fever, it is more often observed in the severe than in the mild cases, as though it were a part of the systemic disturbance incident to the febrile affection and largely proportionate to its severity. [Footnote 99: Maclagan, _Rheumatism: Its Nature, Pathology, etc._, 1881, 287.]