And it appears from the blue tinge given to the fluid by the sulphat of copper, that ammonia or some of its combinations was contained. As it occurred on many former trials, there was no coagulation by heat; a slight sediment fell, after boiling some minutes. As this patient remained in the hospital from the middle of January to the beginning of May, in a state perfectly tranquil, and without the appearance of disarrangement of mind, it is improbable that a so great enlargement of the ventricles, and accumulation of water, could have taken place within the short space of two weeks, it is therefore most likely that the greatest part of this fluid had been previously collected. It may be conjectured that a very gradual accumulation of water (although the quantity be at last considerable) would not affect the sensorium so as a sudden secretion of fluid; or, that a quantity, which at one time had occasioned great disturbance, would by habit become less inconvenient. We are not well informed, but there is reason to believe, that gradual pressure on the brain, will not occasion those serious symptoms which a sudden pressure would excite. CASE XXXI. H. K. a woman, aged thirty, was admitted into the hospital, October 15, 1796. She had then been mad about four months, and her disorder was stated to have supervened on the birth of a child. From subsequent enquiry it was ascertained that her mother had been insane, and that her elder sister had been similarly affected; but from the best information it did not appear that her brothers (she had two) had ever been visited with this calamity. Previously to her admission she had frequently attempted to destroy herself, and had also endeavoured to take away the life of her husband. In the hospital she was extremely violent; supposed her neighbours had conspired to take away her liberty, and became jealous of her husband: she was often naming some female of her acquaintance who had artfully ensnared his affections, and whom he had decked out in her best apparel: she breathed revenge when she should return home, and seemed much delighted with the idea of destroying these favourites, when they were dressed for some excursion with her husband. She had understood that a year was the extent of time that persons were detained in the hospital, and conceived she should be liberated when it had elapsed, to put her menaces into execution. Her disorder being of a dangerous tendency she was retained in the hospital after the period of probation. When she found the hope of gratifying her revenge frustrated, by being kept beyond the time of her expectation, she began to pine away, her appetite diminished, and a cough, with copious expectoration and hectic fever supervened. During the whole period of her bodily disease, she would never acknowledge herself to be ill, and the violence of her mental disorder was unabated. She died of Phthisis Pulmonalis, April 1st, 1798.