ANAESTHESIA 373 



paralyses the parts with which it comes into contact. 

 Acting as an irritant on the nasal and laryngeal mucous 

 membrane, it first slows the breathing, and also reflexly 

 the pulse, often causing coughing at the same time. The 

 fear and excitement caused by the restraint and administra- 

 tion induce irregularity and quickening of respiration, and 

 usually also of the circulation. If given slowly narcosis 

 gradually supervenes, the muscles relax, reflexes are lost, 

 and there is a fall of blood-pressure, but the respiratory 

 movements are sustained steadily, as in the third stage of 

 anaesthesia. Still fuller effects paralyse the medullary 

 centres, respiration becomes slower and feebler, and stops, 

 while pulsation and blood-pressure are lowered. ' The 

 nervous system,' Sir Lauder Brunton states, ' is paralysed 

 in the following order first, the cerebral hemispheres ; 

 next, the grey matter of the cord ; next, the white matter ; 

 next, the reflex power of the medulla oblongata ; next, 

 the automatic power of the respiratory centre ; and lastly, 

 the cardiac ganglia.' 



Medical men and veterinarians generally concur in the 

 belief that chloroform is the most convenient and effectual 

 anaesthetic, and these conclusions have been fully justified 

 by two series of investigations carried out at Hyderabad 

 in 1888 and 1889, and comprising upwards of seven hundred 

 experiments, chiefly on dogs and monkeys, but also on 

 horses, goats, and rabbits. Chloroform was the anaesthetic 

 chiefly used, but ether and mixtures of chloroform and 

 ether were also given. Careful records of every experiment 

 were made, and tracings of the pulse and blood-pressure, 

 registered by a manometer, have been reproduced by 

 photography. The experiments were undertaken to make 

 clear the manner in which chloroform acts, and especially 

 to determine how overdoses kill. With these objects, the 

 chloroform was administered in many different ways, and 

 under very various conditions. Some of the animals were 

 fasted for twenty-four hours ; others were fed with flesh 

 or farinacea ; some had coffee, wine, or other stimulants 

 shortly before inhalation ; most were healthy, a few 

 had cardiac disease, and some had fatty degeneration 

 of the heart, purposely produced by administration of 



