if) Gq 7] 
2. Tuat fome apparently flight fractures do abfolutely require 
its application; in fuch cafes the inner table of the fkull is ge- 
nerally more hurt than the outer, and bad fymptoms do not 
arife till towards the end of a fortnight after the injury. 
3. Tuat fratures with depreflion require the application 
of the trephine, and that from fuch there have been fome 
furprifing recoveries. 
4. Tuat depofites of matter on the membranes or furface of 
the brain require the trephine, though it feldom proves fuc- 
cefsful. 
5. THAT concuffion of the brain, characterifed by inmediate 
Jfiupor and infenfibility, does not require the trephine, unlefs ac- 
companied with evideat depreffion of the fkull or extravafation, 
neither of which produces bad fymptoms for fome days after the 
accident which has given rife to. them. 
Vor. IV. Z. 
