Sir Victor Horsley draws attention to this question in the following manner: ‘If a line be drawn from the frontal eminences to the occipital protuberance, it is obvious that more shock results from operations below that line than from above, and as we proceed from the frontal to the cerebellar pole of the encephalon.’ _The mortality according as to whether the tumour is found or not._ According to Horsley, of 79 cases in which a correct diagnosis was made and the tumour removed, 7 died from shock; whilst in 16 cases inaccurately diagnosed, 6 died--a mortality of 9 per cent. in the first case as against 37 per cent. in the second. The added danger resulting from unsuccessful attempts at finding the tumour must not be advanced as an argument against the palliative operations, for the failure to find and remove the tumour implies diligent search for the neoplasm, with necessary prolongation of operative procedures, and perhaps extensive manipulation of the brain substance. Statistics and experience both afford conclusive evidence that accurate localization is essential for the success of the operation. [39] Paton, _Brain_, vol. xxxiii, p. 67. [40] _Pyschische Störungen bei Hirntumor_, 1903. [41] _Lettsomian Lectures_, by the late Dr. Charles Beevor; Duret, _Tumours of the Brain_; Nothnagel, _Tumours of the Brain_, &c. [42] _Brit. Med. Journal_, March 1, 1908. [43] _Lancet_, July 10, 1909. [44] Crowe, Cushing, and Homans, _Johns Hopkins Bulletin_, May 1910. [45] _Lancet_, April 15, 1904. [46] _Brit. Med. Journal_, October 26, 1906. [47] _Annals of Surgery_, 1907, p. 543. [48] In the event of cessation of respiration during trephining, the skull should be opened and the dura incised with the utmost expedition. The relief of tension so afforded often allows of respiratory recovery--with or without artificial respiration. [49] _Brit. Med. Journ._, 1893, p. 1421. [50] _Surgery of the Brain_, vol. i, p. 117. [51] _Wien. klin. Wochensch._, No. 21, 1907. CHAPTER VIII THE INFECTIVE DISEASES OF THE BRAIN AND MENINGES: ABSCESS OF THE BRAIN, MENINGITIS, LATERAL AND CAVERNOUS SINUS THROMBOSIS, HERNIA CEREBRI ABSCESS OF THE BRAIN Abscess of the brain may be considered under the following headings:-- Multiple abscess. Acute traumatic abscess. Chronic abscess. =Multiple abscess.= Multiple abscess results from the lodgement of infected emboli which, derived from an acute infective osteomyelitis, endocarditis, gangrene of the lung, &c., are carried by the blood-stream to the brain. Multiple abscess of the brain may therefore be considered as part of a general infection. On account of the symptoms dependent on the primary infection and on the secondary pyæmic developments, a diagnosis can seldom be determined, and, even in those rather hypothetical cases in which suspicion may be aroused, surgical interference is quite useless and the prognosis hopeless. It is, therefore, quite unnecessary to discuss the matter further.