‘The less definite the symptoms of compression, the greater the reason to believe that they are caused by the internal table only.’ Before entering into the question of _treatment_ of fractures of the skull, it is essential that allusion should be made to the _temperature in its relation to head-injuries._ The great importance of temperature changes in the consideration of operative treatment will be manifest when discussing the treatment of fractures of the base. =The temperature in its relation to head-injuries.= The various temperature changes observed in cases of head-injury have afforded a subject prolific in discussion. Broca, Battle, Guyon, Walsham, and others have endeavoured to deduce facts from the examination of head cases, but the results have been rather indefinite. In over 300 cases that have come under my observation, accurate records of the temperature charts were obtained, the patients were watched throughout their illness, and in the case of death, the autopsies were attended. The following deductions were made:-- 1. That, for a variable period of time after the injury, the temperature is always subnormal--sometimes so low that it cannot be registered. This is the period of shock. 2. That the patient may die in this state of shock, but that, if he lives, reaction takes place and the temperature rises. 3. That this rise in temperature is, in fatal cases, rapid and progressive. In one case the temperature rose 6° in seven hours, in another 8° in four hours. Death occurs when the temperature is at its highest--anything up to 106°, and even more when registered in the rectum. 4. That the temperature may rise to a moderate height, and there ‘mark time’. This is the ‘crisis’ of the case. A subsequent fall in temperature generally indicates recovery, a further rise usually points to a fatal termination. 5. That the rise of temperature is independent of any special osseous lesion, since similar changes are observed in fractures of the vault and in fractures of the base. 6. That laceration of the brain is present in the majority of cases in which marked temperature changes are observed, but that the changes in temperature are totally independent of any special regional brain-injury. Richet arrives at the conclusion that two hypotheses present themselves, accounting for temperature changes in general: (1) that there are certain temperature regulators in the encephalon which, when excited, become stimulated in function; (2) that the cortical injury acts in a sort of reflex manner on the regulatory centres situated in the pons or bulb. Attention was also drawn to the experiments of Lorin and van Benedin, who, after excising the two cerebral hemispheres of a pigeon, showed that the heat regulatory centre was preserved intact, proving that the corpus striatum is not necessarily the head-office for heat-regulation in general.