(Concluded from page 728.)
The pus may be found outside of the dura-mater, and search should be made for it in this location. If found, and the dura appears to be thoroughly healthy, with no bulging or fluctuation, the operation may cease, and future developments awaited. But if pus is not found outside of the dura, or when found in this situation the dura appears unhealthy, or bulges or fluctuates, a free incision through it should be made, and the brain itself exposed. Pus may be found just inside the dura. If this proves to be the case, and the brain substance appears healthy, and is not bulging or fluctuating, operations may be suspended; but if pus is not found, or, if found, and the conditions just mentioned are present, and the operator is reasonably sure of his diagnosis, investigations must be pushed into the brain proper.
For exploring the