144 SCIENTIFIC ILLUSTRATIONS [Har 



get along by their own exertions if they can find others to carry 

 them ; they are sharp in their own interests, and know quite 

 well when to desert a supporter ; and they are ready to avail 

 themselves of discarded or accidental ailment. MU. 



Happiness is Relative. X 



The Peloncea ccrrugata is remarkable as much for its habits 

 as its shape. It is not fixed to any object, but is as motionless 

 as if it were attached to a rock, and seems to pass a singularly 

 unenjoyable existence. Yet it is doubtlessly happy in its own 

 way, though that way is a very strange one. It lives embedded 

 in the mud, its whole body being sunk, and only the ends of 

 the two apertures projecting into the water. The existence led 

 by some men and women seems almost as much at variance with 

 our antecedent notions of a happy life as is that of this peloncea 

 corrugata. Their sluggish, impassive natures grovel in low 

 pursuits, and never move about amongst the intelligent currents 

 of human society. No doubt their existence has its pleasures. 

 Happiness is a relative thing. The peloncea corrugata would 

 find no gratification in the conditions of life which the mack'erel 

 enjoys. The delights of a clown would be misery to a sage. 



c. s. 



Harmless yet Armed. 



The hedgehog is one of the most harmless animals in the 

 world. Unable or unwilling to offend, all its precautions are 

 only directed to its own security ; and it is armed with a 

 thousand points to keep off the enemy, but not to invade him. 

 While other creatures trust to their force, their cunning, or 

 their swiftness, this animal, destitute of all, has but one 

 expedient for safety ; and from this alone it finds efficient 

 protection. As soon as it perceives itself attacked, it withdraws 

 all its vulnerable parts, rolls itself into a ball, and presents 

 nothing but its defensive thorns to the enemy : thus while it 

 attempts to injure no other quadruped, they are equally in- 

 capable of injuring it. One might suppose that the noisy dog 

 with its sharp teeth was more capable of defending himself 

 than this quiet animal, but it is not so. Indeed it is by no 



