BIOLOGY. 329 



acting as a tonic, and producing, in large doses, severe head- 

 ache. 



Picric Acid. — Picric acid is an efficacious remedy in intermit- 

 tent fevers. Persons affected with such types of fever, upon whom 

 quinine has lost all its beneficial effects by continuous usage of 

 it, — and this is the case with some of our soldiers who return 

 from India, — derive, physicians say, wonderful benefit from the 

 use of picric acid and picrates, as Dr. Aspland has proved to 

 be the case at the military hospital at Dukinfield. The knowl- 

 edge of tliis fact may i)e useful in districts in which poor popula- 

 tions exist, for it affords them a cheap febrifuge ; and, moreover, 

 picric acid is not dangerous, as arsenical preparations are, nor 

 does it derange the stomach like quinine. 



Wounds by the Chassepot Rifie. — Experiments have recently been 

 made at the camp of Lyons on the bodies of dead horses, with the 

 view of ascertaining the precise character of the wounds produced 

 by conical bullets discharged from the Chassepot muskets. It is 

 said that the aperture made by the projectile at the moment it 

 penetrates the flesh is commonly no larger than an ordinary pea, 

 but that the rotary movement of the ball revolving on its axis 

 gradually enlarges its circles until it makes a hole into which a 

 person could thrust the fist. 



Death hy Fire-Damp. — Dr. B. W. Richardson, F.R.S., in in- 

 vestigating the physiological action of the methyl compounds, has 

 particularly observed the action of the hydride of methyl, which 

 occurs naturally in the form of fire-damp in mines, and as marsh 

 gas on land. Seeking first to ascertain what percentage would 

 prove fatal in the aii', he found that even pigeons could live in an 

 air charged with 85 per cent, of the gas, for half an hour. When 

 death finally ensued, it came as a sleep, so gentle that it was de- 

 termined with difficulty when either circulation or respiration 

 ceased. From these observations he concluded that the victims 

 of a mine explosion die an easy but prolonged death, and while 

 tiie knowledge of the first of these truths should inspire thankful- 

 ness, the latter should encourage the rescuing party not to aban- 

 don their exertions even for days after the accident has occurred. 



Means of Recognizing Death loith Certainty. — Dr. E. Martenot, 

 of Lyons, France, has devised a method of deciding the question 

 in cases of doubtful death. It consists in applying the flame of a 

 candle to the flesh of the finger or toe of the patient for a few 

 seconds, until a blister is raised. This invariably takes place. If 

 the blister is filled with serum, life still remains; if the blister is 

 filled with vapor, death has taken place. A dry blister signifies 

 death; a moist blister, life. — L''Union Medicale. 



Antidote for External Poisoning hy Cyanide of Potassium. — This 

 substance is extensively used in electroplating and other arts, 

 where its external poisoning effects produce man}' painful and 

 troublesome ulcers on the hands of the workmen. The foreman 

 of the gilding department of the American Watch Works writes 

 to the Boston " Journal of Chemistry " that experience has taught 

 him the most effectual remedy that can be employed in such cases, 



28* 



