24 THE MICROSCOPE 



near Beyrout, at the close of the year 1880, some particulars of 

 which may be of interest. A wild boar was shot on the 25th 

 of November, and, as the poor people in these parts have not 

 much opportunity of getting animal food, it was distributed as a 

 luxury all round the neighbourhood. Of those who partook of 

 the flesh, 257 persons were more or less affected, and of these 

 six people and two cats died. The following description of the 

 symptoms is given by a physician at Beyrout, who investigated 

 the outbreak. He says : — " From ten to twenty days after eating 

 the meat, the face and extremities became oedematous, the swell- 

 ing extending over the whole body. This was accompanied by 

 severe pain in all the muscles, with more or less fever. These 

 phenomena did not continue more than two or three weeks, 

 and were followed by slow convalesence, with much weakness 

 and lingering muscular pains." 



Another disease — not dangerous, but very unpleasant — the 

 Itch, is shown by the microscope to be caused by a parasitic 

 insect, the Acarus scabiei^ which burrows in the skin, setting up 

 severe and troublesome irritation. 



Several skin affections have been found to depend on the 

 development of microscopic fungi in the epidermis, and the 

 troublesome complaint, Ringworm, is known to be caused by the 

 growth of the Trichophyton tonsurans. It is found in the form of 

 very minute oval, or rounded and perfectly transparent cells, within 

 the bulb and in the central canal of the hair, by the rapid increase 

 of which the fibres of the hair are split up and become quite dry 

 and brittle. 



Among other diseases whose morbid anatomy has been illus- 

 trated by the microscope, we may mention Gout. It depends 

 upon the presence of an excess of uric acid in the system, which 

 is deposited in the joints, and by making a thin section of a gouty 

 joint, and examining it with a ^-inch objective, we may see fine 

 interlacing crystalline needles or prisms of urate of soda, which 

 project into the substance of the healthy cartilage, and which 

 become more highly illuminated, and more or less coloured if we 

 examine them with the polariscope. 



Having now seen some of the uses of the microscope in 

 Physiology and Morbid Anatomy, we must in the last place look 



