FREE BOOKS

Author's List




PREV.   NEXT  
|<   65   66   67   68   69   70   71   72   73   74   75   76   77   78   79   80   81   82   83   84   85   86   87   88   89  
90   91   92   93   94   95   96   97   >>  
he water in washing was in this case also very small, the potash required for neutralizing equaling 1.02 per cent. of the weight of oil. I found that the cakes of acids were solid at 36 deg. C., and were completely melted at 39 deg. On solution in alcohol, and digestion for two days with animal charcoal, the color was much diminished, and on the liquid being filtered and cooled to 0 deg. C., an abundance of small white crystalline plates separated out, which, when dried, melted at 67 deg. C. The crude fatty acids turn black with sulphuric acid, as the oil does, and yield a similar substance with nitric acid. It is similar in appearance, but differs in that it melts at about 50 deg. C., and is soluble in glacial acetic acid, which is not the case with the substance from the oil. These fatty acids crystallize on cooling, in a most characteristic and beautiful way, forming wavy circular plates totally unlike any that I have seen before. The above experiments may, I think, be taken as conclusive as to the nature of tea oil and cabbage oil. The former may certainly be considered a useful lubricating agent for the finer kinds of machinery. The work upon wood oil is not yet sufficiently complete to show us the nature of its proximate constituents. I am continuing the examination of this oil. Perhaps I need scarcely add that there is no connection between this "wood oil" and the Gurgun balsam, the product of _Dipterocarpus turbinatus_, which is also known as "wood oil." * * * * * THE OTOSCOPE. Prof. Leon Le Fort has recently presented to the Academy of Medicine, in the name of Dr. Rattel, a new otoscope, which we illustrate herewith. The first person to whom the idea occurred to illuminate the ear was Fabricius d'Acquapendentus (1600). To do this he placed the patient in front of a window in such a way as to cause the luminous rays to enter the external auditory canal. It was he likewise who conceived the idea of placing a light behind a bottle filled with water, and of projecting its concentrated rays into the ear. In 1585 Fabricius de Hilden invented the speculum auris. This instrument was employed by him for the first time under the following circumstances: A girl ten years of age had in playing introduced a small glass ball into her left ear, and four surgeons, called in successively and at different times, had been unable to extract it. Meanwhile the little pat
PREV.   NEXT  
|<   65   66   67   68   69   70   71   72   73   74   75   76   77   78   79   80   81   82   83   84   85   86   87   88   89  
90   91   92   93   94   95   96   97   >>  



Top keywords:

plates

 

Fabricius

 

nature

 
substance
 
melted
 

similar

 
occurred
 

window

 

Acquapendentus

 

patient


illuminate
 

Medicine

 

turbinatus

 

OTOSCOPE

 

Dipterocarpus

 
product
 

connection

 

balsam

 

Gurgun

 
Rattel

otoscope

 
herewith
 

illustrate

 

recently

 

presented

 

Academy

 

person

 
bottle
 

playing

 

introduced


circumstances

 

extract

 

unable

 

Meanwhile

 

surgeons

 

called

 

successively

 

placing

 

filled

 

conceived


external

 

auditory

 

likewise

 

projecting

 

concentrated

 

instrument

 
employed
 

speculum

 

invented

 

Hilden