436 OnEFFUSION 



means gave vent to a quantity of pus of a greenifli white 

 colour ; the pain ceafed entirely, the patient was loon cur- 

 ed ; and fince has enjoyed a perfedt ftate of health. 



The preceding obfervation cleai'ly flicws the dura mater 

 had been long I'eparated from the fcull by the matter, and 

 proves that the feparatlon of this membrane is not dan- 

 gerous. 



It will be faid perhaps that this feparation did not pro- 

 duce any bad effedt becaule it took place gradually : my 

 anfwer is, an effufion occalioned by violent blows is fud- 

 denly formed, it forces the dura mater from the cranium 

 with violence, and feparates it fometimes to a great extent. 

 It may be again objedted that nature though acting haftily, 

 manages in a manner art cannot imitate in feparating the 

 dura mater from the fcull. 1 will oppofe this objedlion 

 by experience, and not argument. 



The 29th of March 1795, there was brought to the 

 French hofpital eftabliflied in this city, a man about thirty- 

 eight years of age, of a middle fize and very robuft con- 

 ftitution : he was comatofe, his face inflated and difco- 

 loured with ecchyniofis, his body covered with bruifes, 

 and many wounds made with pointed inftnmients : thofe 

 who brought him, told me he had been ftruck with an 

 iron bar which fraftured his fcull j and had been trepan- 

 ned on the fpot. 



After uncovering the head, it was wafhed and fhaved : 

 and I found the trepan had been applied on the upper part 

 of the right parietal bone, about an inch from the coronal 

 future. 



1 took away, with the lenticular knife, pieces of the 

 internal plate which wounded the dura mater, and enlarged 

 the wounds in the diredion of the fradure on which the 

 trepan had been applied ; it proceeded from the fagittal fu- 

 ture, and defcended almofl in a right line into the temporal 

 region, at the upper part of which I bounded my incifion, 



although 



