14 SCIENTIFIC RECREATIONS. 



experiment of the cataleptic cock was first described under the name of 

 Experimentum Mirabile, by P. Kircher, in his Ars Magnet, published at 

 Rome in 1646. It evidently belongs to the class of experiments which 

 were performed at the Salpetriere asylum at Paris, by M. Charcot, on 

 patients suffering from special disorders. It must now be evident to our 

 readers that our scientific occupations were sufficiently varied, and that we 

 easily found around us many objects of study. When the weather was wet 

 and cloudy we remained indoors, and devoted ourselves to microscopical 

 examinations. Everything that came under our hands, insects, vegetables, 

 etc., were worthy of observation. One day, while engaged over a micro- 

 scopical preparation, I was making use of one of those steel points generally 



Fig. 9. Thorn of a rose, and wasp's sting through a microseope (magnified 500 diameters). 



employed in such purposes, when happening to pass it accidentally beneath 

 the microscope, I was astonished to see how rough and uneven it appeared 

 when highly magnified. The idea then occurred to me to have recourse 

 to something still more pointed, and I was thus led to make comparisons 

 between the different objects represented in figs. 8 and 9. It will here 

 be seen how very coarse is the product of our industry when compared 

 with the product of Nature. No. I of fig. 8 represents the point of 

 a pin that has already been used, magnified 500 diameters. The point 

 is evidently slightly blunted and flattened. The malleable metal has 

 yielded a little under the pressure necessary to make it pass through a 

 material. No. 2 is a little more pointed ; it is a needle. This, too, will be 

 seen to be defective when regarded by the aid of the microscope. On the 

 other hand, what fineness and delicacy do the rose thorn and wasp's sting 



