42 6 POPULAR SCIENCE MONTHLY. 



has scarcely been investigated. As a curiosity, yet as a possible venture, 

 a parallelism may be suggested between the stridulations of a cricket, 

 which have been counted as occurring at the rate of between two and 

 three chirps per second* and the number of pulse waves peculiar to 

 very active insects or one hundred and fifty closures of the heart valves 

 in one minute.t 



Inspecting in a very cursory manner the higher phylums of the 

 animal kingdom, the authority of numerous investigators can be given 

 for the perfect rhythmic quality of bird songs. The writer can vouch 

 for it that the cackle of one guinea hen during an entire summer went 

 with clock-like regularity at the rate of eighty-eight to ninety-two 

 cackles per minute. The faster cackling being a laughably accurate 

 sign of the growing excitement attendant on the laying of an egg, 

 said by the owner to occur at about eleven o'clock every morning. 



The scientific study of rhythm, so far as man is concerned, has 

 been approached almost wholly from the side of its conjunction with 

 literature. Looked at from that side, it is not strange that the testi- 

 mony could never be mathematically exact and emphatic. The only data 

 which are of sufficient accuracy to prove that the rhjiihmic phenomena 

 of pulse first impressed on our consciousness that which can accurately 

 be called rhvthm, are to be found in the metronomic denotations «f 

 musical compositions. It is there and there only that the brain has 

 been able systematically to externalize the rhythm most natural to it 

 with a sense of method and order approximating instrumental exacti- 

 tude and capable of an exact expression and measure in number. These 

 furnish only a trace, but a trace sufficient when one keeps in mind 

 the havoc that conscious intellect can always play with things strictly 

 natural. 



While making a bibliographical search for anything treating of this 

 musical side of the subject, one suggestive title only was found. It was 

 under 'pulse' in the Larousse Encyclopedia and covered the subject to 

 a degree alarming to a new and anxious investigator. It 'Nouvelle 

 methode facile et curieuse pour connaitre le pouls par les notes de la 

 musique. ' (New method, easy and curious for gauging the pulse bv 

 musical notes.) Frangois Nicolas Marquet, Nanc}', 1747. ^Vhen 

 found, the quaint little book proved lamentably insufficient. In its 

 time there was neither metronome nor sphygmograph. 



In the introduction to this little treatise which in its day seems to 



have created quite a stir — 'amateurs in search of novelties bought it for 



fun, and kept it by good taste,' M. Marquet naively tries to disarm 



his critics by saying that he already seemed to hear them object: 'it is 



certainly a very bizarre matter this learning to know the pulse by 



musical notes,' adding, 'one could answer them, it is not more strange 



*~'~Proc. Boston Soc. Nat. Hist., October 2371867.' 



t'A Text-book of Entomology,' Packard, Macraillan, 1898, p. 401. 



