THE SERPENT. 



413 



serpents, is very different from that of the 

 earth-worm, or the naked snail. The serpent, 

 as was said above, has a back-bone with num- 

 erous joints, and this bone the animal has a 

 power of bending in every direction, but with- 

 out being able to shorten or lengthen it at 

 pleasure. The earth-worm, on the other 

 hand, has no back-bone ; but its body is com- 

 posed of rings, which, like a barber's puff, it 

 can lengthen or shorten as it finds necessary. 

 The earth-worm, therefore, in order to move 

 forward, lengthens the body; then, by the fore 

 part clings to the ground, where it has reached, 

 and then contracts and brings up its rear : 

 then, when the body is thus shortened, the 

 fore part is lengthened again for another pro- 

 gression ; and so on. The serpent, instead of 

 shortening the body, bends it into an arch ; 

 and this is the principal difference between 

 serpentine and vermicular progression. 



I have instanced this motion in the viper, 

 as most easily discerned ; but there are many 

 serpents that dart with such amazing swift- 

 ness, that they appear rather to leap than 

 crawl. It is most probable, however, that no 

 serpent can dart upon even ground farther 

 than its own length atone effort. Our fears, 

 indeed, may increase the force of their speed, 

 which is sometimes found so fatal. We are 

 told by some, that they will dart to a very 

 great distance ; but this my inquiries have 

 never been able to ascertain. The manner of 

 progression in the swiftest serpent we know, 

 which is the jacalus, is by instantly coiling 

 itself upon its tail, and darting from thence to 

 its full extent ; then carrying the tail as quick 

 as lightning to the head, coiling and darting 

 again ; and by this means proceeding with 

 extreme rapidity, without ever quitting the 

 ground. Indeed, if we consider the length 

 and the weakness of the back-bone in all these 

 animals ; ifwe regard the make of their verte- 

 brae, in which we shall find the junctures all 

 formed to give play, and none to give power; we 

 cannot be of opinion that they have a faculty 

 of springing from the ground, as they entirely 

 want a fulcrum, if I may so express it, from 

 whence to take their spring ; the whole body 

 being composed of unsupported muscles and 

 joints that are yielding. It must be confessed, 

 that they dart down from trees upon their prey ; 

 but their weight alone is sufficient for that 

 purpose without much effort of their own. 



Though all serpents are amphibious, some 

 are much fonder of the water than others ; and, 

 though destitute of fins or gills, remain at the 

 bottom, or swim along the surface with great 

 ease. From their internal structure, just 

 sketched above, we see how well adapted they 

 are for either element ; and how capable their 

 blood is of circulating at the bottom, as freely 

 as in the frog or the tortoise. They can, how- 



ever, endure to live in fresh-water only ; for 

 salt is an effectual bane to the whole tribe. 

 The greatest serpents are most usually found 

 in fresh-water, either choosing it as their fav- 

 ourite element, or finding their prey in such 

 places in the greatest abundance. But that 

 all will live and swim in liquids appears from 

 the experiment of Rhedi ; who put a serpent 

 into a large glass vessel of wine, where it 

 lived swimming about six hours ; though, when 

 it was by force, immersed and kept under that 

 liquid, it lived only one hour and a half. He 

 put another in common water, where it lived 

 three days ; but when it was kept under water, 

 it lived only about twelve hours. 1 Their 

 motion there, however, is perfectly the reverse 

 of what it is upon land ; far, in order to sup- 

 port themselves upon an element lighter than 

 their bodies, they are obliged to increase their 

 surface in a very artificial manner. On earth 

 their windings are perpendicular to the sur- 

 face ; in water they are parallel to it ; in other 

 words, if I should wave my hand up and 

 down, it will give an idea of the animal's pro- 

 gress on land ; if I should wave it to the right 

 and left, it will give some idea of its progress 

 on the water. 



Some serpents have a most horrible foetor at- 

 tending them, which is alone capable of inti- 

 midating the brave. This proceeds from two 

 glands near the vent, like those in the weasel 

 or polecat ; and, like those animals, in propor- 

 tion as they are excited by rage, or by fear, the 

 scent grows stronger. It would seem, how- 

 ever, that such serpents as are most venomous, 

 are least offensive in this particular ; since the 

 rattlesnake and the viper have no smell what- 

 ever : nay, we are told that at Calicut and 

 Cranganon, in the East Indies, there are some 

 very noxious serpents who are so far from being 

 disagreeable, that their excrements are sought 

 after, and kept as the most pleasing perfume. 

 The Esculapian Serpent is also of this number. 



Some serpents bring forth their young alive, 

 as the viper ; some bring forth eggs, which are 

 hatched by the heat of their situation : as the 

 common black snake, and the majority of the 

 serpent tribe. When a reader, ignorant of 

 anatomy, is told, that some of those animals 

 produce their young alive, and that some pro- 

 duce eggs only, he is apt to suppose a very 

 great difference in the internal conformation, 

 which makes such a variety in the manner of 

 bringing forth. But this is not the case : 

 these animals are internally alike, in whatever 

 manner they produce their young ; and the 

 variety in their bringing forth is rather a 

 slight, than a real discrimination. The only 

 difference is, that the viper hatches her eggs, 

 and brings them to maturity within her body ; 



1 Rhedi, Exper. p. 170. 



