SPECIFIC CATARRHAL DISEASE, OR DISTEMPER. 105 



tion, in the popular and usual acceptation of the term ; by which 

 is understood, an inflammation of the air-passages productive of 

 defluxion. But as the true etymology of catarrh extends to in- 

 flammation of the mucous surfaces of the body generally, and as 

 distemper deserves the full extent of signification, we shall now 

 have to follow it as it extends itself over the one or the other of 

 these mucous surfaces principally, or as it diffuses itself universally 

 through the whole : dependent on which election, are the various 

 types which the future progress of the disease assumes. 



The transmission of the affection to the brain or its meninges^ 

 we are led to suppose, takes place not only by the epileptic symp- 

 toms of some cases, or the chorea and paralysis of others; but 

 even more certainly by the morbid appearances which present 

 themselves after death. However, whether this occurs by conti- 

 nuity of substance, or by metastasis, we are not aware ; although 

 analogically it may be supposed to be by the former, in which case 

 the inflammation may shape its course from the orbitary fossae, or 

 it may follow the more likely tract of the pituitary sinuses. It is 

 not, however, unlikely, that in some few cases a true metastasis 

 does occur ; for we occasionally have a very sudden attack of epi- 

 lepsy, without any of those premonitory symptoms which usually 

 predict, with malign certainty, the distempered fits ; and there is 

 more reason to conclude this, for a single fit, not followed up by 

 another, particularly when it appears early in the complaint, is 

 often not injurious ; and therefore we may suppose it the conse- 

 quence of a sudden metastasis, which as quickly returns to its ori- 

 ginal seat. In the ophthalmia and acute founder of horses, and in 

 the gout of the human subject, these rapid transitions of disease 

 are not uncommon. 



Our knowledge of cerebral aflfections is very confined ; but we 

 have reason to suppose that the nature of morbid attacks on the 

 sensorium and its dependencies are varied like those of other 

 organs. Probably also much may depend on the immediate por- 

 tion affected, as whether it be the cerebral substance or its matrices : 

 nor is it, therefore, unreasonable to conclude, that to this it is 



