"Many practitioners give the mild preparations of mercury, and particularly calomel, freely in this disease, under a notion of its having some specific power in subduing it; but it never should be so used, excepting in cases where the disease is symptomatic of some functional disturbance in the liver and other chylopoietic organs, where it is calculated, in conjunction with the local bleeding, &c. to afford the most important service." With a view of pointing out some characteristic sign, by which to distinguish those cases in which the affection of the bowels is primary from those in which it is secondary, he remarks-- "The condition of the stools at the period when a child is labouring under the disease, will afford to such persons but an imperfect notion of its true nature; for the disturbance of the brain will often create a disorder in the secretions, both of the liver and the other chylopoietic organs, producing green looking stools; and there is often a congestive state of the brain for a short time preceding the full development of the idiopathic excitement, which may, in like manner, by reacting upon the liver, create a disorder there. In cases, however, which are symptomatic of this cause, the chylopoietic disturbance will be found to have existed several days or even weeks; and the origin of the disorder, in like manner, may be commonly traced to some irregularity of diet, or other obvious causes, and frequently in infants to those which are connected with premature weaning; and sometimes even the cerebral disorder itself will have been only the last of a series of effects in the system, to which such disturbance had given rise." Agreeably to Dr. A., it is not proper to discontinue those means, immediately upon the occurrence of what appears to be symptoms of effusion, since, frequently, these symptoms, as it respects the effusion, will immediately manifest their fictitious character, and disappear under a treatment no wise adapted to such a state, and with a rapidity, too, which equally betrays their true nature. He notices, though we believe not in its proper place, a modification of the disease in which the effusion takes place in the cellular membrane of the substance of the brain, and thinks this species more likely to be recovered from than when the water accumulates in the ventricles. He concludes this section by remarking, that