STAGGEliS. 11 



Encephalic inflammation may confine its attack either to the 

 membranes or to the substance of the brain, or both together may 

 be affected by it : even in this latter case the inflammatory action 

 probably arises in one, and afterwards extends to the other, though 

 still raging in the part first attacked with greater violence than in 

 that which has become secondarily, or sympathetically, or by con- 

 tiguity, affected. From all the circumstances connected with mad 

 staggers, there appears reason to believe that the membranes are 

 mostly the principal or primary seat of the inflammation, and that 

 the brain to the extent that it is affected, if at all, is but secondarily 

 so : not that we recognise any symptoms during life that we can rely 

 upon as safely directing -us either in one case or the other, but that 

 the appearances after death are commonly such as especially denote 

 membranous disease. There is no symptom recognised even in 

 human medicine as perfectly diagnostic between the membranous and 

 cerebral affections: the former is said to be " marked by acute pain, 

 delirium, and convulsions; the latter by muscular contractions, 

 alternating with and followed by paralysis ;" but the best physi- 

 cians acknowledge the difficulty they feel in drawing a correct 

 diagnosis. The usual consequence of inflammation of a serous 

 membrane is effusion of a straw-coloured fluid, which we in com- 

 mon language denominate "water;" and every practical veterina- 

 rian knows that nothing is so common as, after death from mad 

 staggers, to meet with the ventricles, and sometimes the cavities 

 within the olfactory nerves as well, filled with this water; either 

 in a state of beautiful pellucidity, or else stained with blood, or 

 perhaps turbid from admixture of pus : these cavities, I need not 

 add, being lined with pia mater. Now and then water is found 

 included between the membranes themselves, stagnating upon the 

 surface of the brain. Not, however,^ that this effusion is to be con- 

 sidered as an infallible sign of inflammation having existed; for, 

 as has been observed by pathologists of unquestionable reputation, 

 " inanition and repletion both dispose to effusion within the head." 

 When the inflammation has pervaded the brain itself, its substance, 

 when cut into, will display spots of blood no larger than the pricks 

 of a pin or needle ; and these will be more or less numerous and 

 extensive according as the inflammatory action has raged with more 



