184 NON-INFLAMMATORY DISEASES OF BONES. 



above mentioned. Externally, there was nothing to denote 

 this alteration in the bones, and the only observable change of 

 structure was wasting of the masseter muscles, and, as a con- 

 sequence, an apparent undue prominence of the zygomatic 

 ridge. My prognosis was unfavourable, and in a few days 

 afterwards he died comatose. On making an examination, the 

 brain was found very white, and greatly enlarged, the enlarge- 

 ment partaking of the character of a fibrous development ; the 

 dura mater was much thickened, in some places upwards of 

 an inch in thickness. The lateral ventricles were nearly 

 obliterated by growth of fibrous tissue in the brain substance. 

 The cranial nerves, with the exception of the fifth pair, were 

 normal in appearance; but this (the fifth) pair were greatly 

 enlarged, not only in their general bulk, but in each of their 

 fibres, which were coarse, stringy, and distinctly separated by 

 an abundance of fibrous tissue. As already stated, the eth- 

 moidal bone was absorbed, and the brain and thickened dura 

 mater filled the frontal sinuses. 



How can this strange disease be accounted for ? If the 

 patient had been human, syphilis or mercury would have been 

 blamed ; but here was a patient that had never been mer- 

 curialized, never syphilitic. It might with reason be said that 

 the attack of phrenitis had led to the brain enlargement, and 

 that the absorption of the cranial bones had resulted from 

 internal pressure from the growth of the cerebral mass. But 

 how about the facial bones ? Was the altered structure of the 

 fifth pair of nerves sufficient to account for this ? My colleague, 

 Dr. Young, is of opinion that the disease was primarily in the 

 bones, and that the pathological alterations found in the brain 

 and nerves were a result of the osseous change. 



OSTEO-POROSIS. 



This disease was first described in this country by Professor 

 Vamell, in the Veterinarian of 1860. It appears from his 

 careful and elaborate report that at one farm near Eeading, 

 no fewer than six horses had been affected Avith this strange 

 malady when he reported upon it. Since then, however, many 

 practitioners have witnessed it, and all agree that Mr. Varnell's 

 report is a most faithful one. Mr. Anderson of Glasgow, and 



