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mata upon the nerves is fufficient to give 
rife to a great variety of accidents, or in 
other words, of different difeafes. 
We have already obferved, that the brain 
conffantly re-adts, and that a great variety 
of changes in the animal economy pro® 
ceeds from, this re-adtion. Hence it is 
natural to believe, that this organ does 
every thing in difeafes. 
A difeafe frequently changes its eha® 
radter in the fame individual, either fpon® 
taneoufly or by fome change in the air, 
or diforderly condud of the patient, or 
fome miflake of the phyfician. 
Sydenham fays, that it is difficult to 
recognize intermittent fevers, particularly 
autumnal ones, as they appear like eon® 
tinued fevers, and one can fcarcely difcover 
any remiffion in them, but by degrees they 
perfedUy intermit, and put on a form .en¬ 
tirely agreeable to the feafon of the year. 
And he likewife obferved, that fome** 
times fevers after one or two paroxyfms 
