2. The _rheumatism_. Of this I have known two instances. Dr. Lettsom has recorded a case from the same cause[49]. The pains in the limbs, which are supposed to be the effect, I suspect are frequently the cause of the disease. [49] Medical Memoirs, vol. I. p. 174. 3. The _pulmonary consumption_. Of the connection of this disease with an internal dropsy of the brain, Dr. Percival has furnished us with the following communication[50]: "Mr. C----'s daughter, aged nine years, after labouring under the phthisis pulmonalis four months, was affected with unusual pains in her head. These rapidly increased, so as to occasion frequent screamings. The cough, which had before been extremely violent, and was attended with stitches in the breast, now abated, and in a few days ceased almost entirely. The pupils of the eyes became dilated, a strabismus ensued, and in about a week death put an end to her agonies. Whether this affection of the head arose from the effusion of water or of blood, is uncertain, but its influence on the state of the lungs is worthy of notice." Dr. Quin likewise mentions a case from Dr. Cullen's private practice, in which an internal dropsy of the brain followed a pulmonary consumption. Lieutaud mentions three cases of the same kind[51], and two, in which it succeeded a catarrh[52]. [50] Essays, Medical, Philosophical, and Experimental, vol. II. p. 339, 340. [51] Historia Anatomica-Medica, vol. II. lib. tertius. obs. 380, 394, 1121. [52] Obs. 383, 431. 4. _Eruptive fevers._ Dr. Odier informs us[53], that he had seen four cases in which it had followed the small-pox, measles, and scarlatina. Dr. Lettsom mentions a case in which it followed the small-pox[54], and I have seen one in which it was obviously the effects of debility induced upon the system by the measles. [53] Medical Journal. [54] Medical Memoirs, vol. I. p. 171. 5. _Worms._ Notwithstanding the discharge of worms gives no relief in this disease, yet there is good reason to believe, that it has, in some instances, been produced by them. The morbid action continues in the brain, as in other cases of disease, after the cause which induced it, has ceased to act upon the body. 6. From the dissections of Lieutaud, Quin, and others, it appears further, that the internal dropsy of the brain has been observed to succeed each of the following diseases, viz. the colic, palsy, melancholy, dysentery, dentition, insolation, and scrophula, also the sudden healing of old sores. I have seen two cases of it from the last cause, and one in which it was produced by the action of the vernal sun alone upon the system.