THE INTERNAL ENVIRONMENT 221 



158. Influence of Physiological Troubles. In all the preceding 

 circumstances, the physiological functions (circulation, respira- 

 tion, etc.), were presumed to be normal. The blood fulfils its 

 function as the vehicle of the oxygen and is the purifying stream 

 of the tissues. Therefore a compression which impedes the cir- 

 culation (tight clothes or defective attitudes when working ( l ) 

 decreases the muscular activity. Anaemia aggravates this 

 symptom and produces fatigue ( 2 ) ; the fibres and nervous cells 

 becoming less excitable, ( 3 ) without doubt through insufficiency of 

 oxygen. 



Nothing must interfere with the respiration which assures the 

 constant supply of oxygen. The accumulation of carbonic gas 

 in the blood as a consequence of incomplete expiration, as some- 

 times happens in the course of work, causes muscular weakening 

 of toxic origin, ( 4 ) and lowers the nervous excitability. ( 5 ) An 

 intoxication, from the same cause, produces breathlessness ; 

 this happens in work which is so rapid that insufficient time is 

 given for the elimination of all the carbon dioxide ( 112). 



It is an accepted fact that fatigue accompanies this toxic 

 phenomenon that has its source in the blood. For instance, the 

 poisons in the urine and sweat will injure the organism specially 

 the muscular activity unless they are eliminated. ( 6 ) The 

 cleanliness of the skin and a suitable quantity of drink assist 

 that elimination. 



Returning to one of the causes of fatigue, auto-intoxication 

 ( 147), it will be noted that the muscular power of a subject 

 lessens >vith fatigue.( 7 ) Extreme fatigue leads to exhaustion and 

 then grave troubles, with symptoms of momentary paralysis 

 show themselves ( 8 ) ; some of the muscular and nervous fibres 

 being lacerated internally. ( 9 ) Often contraction appears, giving 

 pain for some time. Over-exertion can be fatal. The example 

 of the soldier of Marathon- see the admirable statue in the 

 gardens of the Tuileries by the sculptor Cortot who, after running 

 an almost superhuman race to bring the tidings of victory, fell 



(!) Atwater and Benedict (Bulletin, No. 136, p. 180, 1903), etc. 



( 2 ) A. Maggiora (Arch. Ital. Biologie, vol. xiii., p. 217) ; Jensen (Pfliiger's 

 Arch., vol. Ixxxvi., p. 47, 1901). 



( 3 ) Aducco (Arch. Ital. Biol., vol. xiv., p. 136, 1890 ; Baglioni (ibid., vol. 

 xlii., p. 83, 1904). 



( 4 ) Lothak de Lotha (Comptes Rendus Acad. Sc., Aug., 1902). 



( 5 ) G. Weiss (Comptes Rendus Biol., 1900, p. 444 ; Journal de Physiol., 

 1903, p. 239). 



() Aducco (Arch. Ital. Biol., vol. x., p. 1, 1888) ; Casciani (La Riforma 

 Medica, 1896, June). 



( 7 ) Benedicenti, loc. cit. 



( 8 ) Treves (Arch. Ital. Biol., vol. xxx., p. 1, 1898). 



( 9 ) Th. Hough (Amer. Journ. oj Physiol., vol. vii., p. 76, 1902). 



