DIATOMS 117 



curve-making used to astonish every one who saw 

 his work. So closely did Mr. Perigal's handiwork 

 resemble the tracery done by the harmonic pendulum 



Fig. 36. Coscinodiscus radiatus. A Diatom enlarged several hundred diameters. 



that one was frequently mistaken for the other. The 

 results in each case were enclosed within an area of a 

 few inches. 



In addition to patterns and devices thus produced, 

 there are the charming designs accomplished by the 



