678 THE POPULAR SCIENCE MONTHLY. 



seems to me the neglect of a source of inspiration that one can ill 

 afford to slight. Pursued in the spirit that I have tried to in- 

 dicate, as a natural extension of the experimental knowledge 

 of childhood, and through the medium of a few substances 

 thoroughly studied, I venture to recommend it quite as highly as 

 a means of culture, as an end valuable in itself. It would be an 

 easy task to extend such considerations indefinitely ; but I want 

 rather to open the right door into chemistry, than to decorate its 

 vestibule. " It is a foolish thing," says the author of the Book 

 of Maccabees, " to make a long prologue and to be short in the- 



story itself." 







THE PHYSIOGNOMY OF THE MOUTH. 



By TH. PIDEKIT. 



THE muscles of the mouth have a triple function. They serve- 

 in the articulation of sounds, and assist the activity of the 

 taste and the hearing. Our present study is limited to the move- 

 ments of the buccal muscles, which have to do with the taste. 

 Taste is the earliest developed of all our senses, and abides with 

 us from the first to the last hour of life. No other sense controls 

 man so early or with so much power ; none remains so long faith- 

 ful to him. 



The lips may be regarded as a flat, circular muscle placed in 

 front of the buccal cavity, cleft horizontally in the middle, with 

 a moist, ruddy mucous membrane covering the edges of the open- 

 ing thus formed. Not regarding now the muscles of the lower 

 jaw, the mouth is closed by the contraction of the orbicular mus- 

 cle of the lips, and opened by antagonistic muscles which are fixed 

 on its outer edge. The mouth is, then, destined to undergo very 

 great variations of form ; and, by virtue of this variety of its 

 movements, it enjoys at least as much importance as the eyes in 

 whatever concerns the mimetic expression of the countenance. 



When any object perceptible to the taste is placed upon the 

 tongue at rest, the sensation of the contact is vague and im- 

 perfect. It is only when the upper face of the tongue is pressed 

 against the osseous vault of the palate that a complete impression 

 of the object can be made upon the nerves of taste, the extremi- 

 ties of which abut upon the caliciform papillae of this surface. 

 Hence, when in mastication we inopportunely encounter anything 

 of disagreeable taste, we at once separate our jaws to get the tongue 

 as far as possible from the palate or to prevent any further rub- 

 bing of the upper face of the tongue and repetition of the bad 

 taste. The movement of the jaws is accompanied by a corre- 

 sponding movement of the mouth. The upper lip is removed 



