8 On the Influence of Air 



an infant's being whipped into life, though the contrary 

 might have occurred to their observation. 



This case shows, that it is not material to what part of 

 the body the stimulus is applied, provided it be sufficient 

 to rouse the dormant excitability. The uniform effect 

 of any superior stimulus, whether through the medium 

 of the passions, or by the direct application of any agent 

 capable of exciting the natural motions or actions of the 

 system, is an involuntary contraction. Hence the deep 

 full inspiration accompanying restoration from syncope, 

 and that succeeding surprise, or the application of cold, 

 water to the system, or the wounding even of the most 

 extreme part of the body by the sudden application of any 

 irritating substance, particularly exemplified in the prick 

 of a pin. Reaumur relates a case of a subject restored 

 to respiration similar to the revival of the hybernating 

 animals by the mere application of caloric alone. 



By these and similar cases it is rendered evident, that 

 the form of action produced by any stimulus depends upon 

 the excitability of the animal at the time of its applica- 

 tion. Hence the extraordinarj influence of certain sti- 

 muli in states of accumulated irritability, as of light and 

 water in cases of hydrophobia; and, in instances, even the 

 most delicate aroma becomes as destructive as the deadly 

 exhalations from the Grotto del Cani. 



Now the excitability of the nascent state is at its maxi- 

 mum, as is proved by the greater irritability of infants 

 compared with that of adults, and the less quantity of 

 stimulus necessary to bring all their powers into action. 



