981 



SWIMMING. 



SWIMMING. 



turning himself round on his back in the water than in turning 

 himself in hia bed. 



Some persons can accomplish swimming on the side, and others on 

 the back, without using the legs; and many other feats, such as 

 with the arms acting in different directions as seen in tig. 5, and again 



Fig. 5. 



with one hand alone. In diving, two methods are recommended : 

 one by leaping into the water with the feet downwards, the other 

 head foremost ; the former is most desirable in shallow water, the 

 latter when the head is subject to giddiness and fulness of blood. 



Pig*. 6 and 7 show the attitude preparatory to plunging into the 

 water, and./iy. 8 the position of the limbs in diving to the bottom of 

 the ri 



Figs. 6, 7, and 8. 



The position of greatest ease in the water is floating. The body 

 lies on the back, with the face only above the water ; the limbs arc 

 perfectly quiescent, and extended as in fig. 9. This state can only 

 be maintained when the specific gravity of the body is less than that 

 of the water. 



Fig. 9. 



Sea-water, being heavier than that of rivers, is best calculated to 

 support a person in swimming, and those who are specifically heavier 

 than river-water may be sustained in a floating position in sea-water. 

 It may be observed that man being so nearly of the same specific 

 gravity as water, and air being nearly 1000 times lighter, that a few 

 cubic inches of air in a bag are sufficient to keep one who cannot 

 swim permanently at -its surface; or a few pounds of cork fastened 

 to the body will accomplish the same object : and it is astonishing 

 that, notwithstanding the great number of persons who are annually 

 drowned in the Thames alone, no means are adopted to provide some 

 such simple method for sustaining the body in water by boatmen ; 

 and still more that we hear of watermen being frequently drowned in 

 consequence of not having learned to swim. Swimming ought to 

 form a part of our physical education ; all our youth of both sexes 

 may do so with advantage, for the purpose of cleanliness and to 

 increase their health and strength, ai well as to provide a safeguard 

 against subsequent accidents. 



Th? specific gravity of nearly all Mammiferous Quadrupeds is less 

 than that of water, and hence they are capable of floating on its 

 surface without requiring the interposition of the limbs. We have 

 familiar examples of the specific gravity of quadrupeds in the horse, 



dog, cat, deer, &c. If, for instance, we cause either of the above- 

 named animals to be thrown into deep water, we observe that they 

 speedily rise to the surface, and remain there as long as the limbs are 

 quiescent, and when the limbs move they strike out in the proper 

 direction with precision, although they may never previously have 

 been out of their depth in water. But if we inquire how it happens 

 that these animals are enabled, without the aid of experience, to swim 

 at once the first time they are plunged into water, we find on investi- 

 gation that the limbs of Mammiferous Quadrupeds move in water 

 precisely as they do on land, and no new action, either as regards 

 direction or order, is required, as is the case with man, to enable them 

 to swim ; and as they are specifically lighter than water, they need no 

 force to be employed to keep them above the surface. In hunting 

 the stag or the fox, it is not an uncommon occurrence for the animal, 

 when hard pressed in the chase, to plunge into a stream and swim 

 across the water, the hounds following. The huntsman, relying on 

 tho tact of his horse, plunges fearlessly with it into the water, and 

 arrives safely on the opposite bank. In these cases the horse carries 

 its rider above the surface, thus showing that the specific gravities of 

 the man and horse combined are much less than that of the water. 



Most of the Mammiferous Animals are amphibious, and possess 

 the faculty of sustaining themselves during lengthened periods under 

 water. Of these, several species have the feet furnished with a mem- 

 brane between the fingers and toes ; such, for example, as the Otter 

 tribe. These animals are excellent swimmers, and their agility in the 

 water is surprisingly great. It appears that nearly all mammiferous 

 animals can swim if necessitated to do so ; and it should be borne in 

 mind that this has been accounted for by their being gifted with two 

 qualities essential in swimming the one arising from specific gravity, 

 and the other from the circumstance of the natural movements of the 

 limbs being the same both on land and in water. 



Amongst the Birds, those of the order Natatores are, as their generic 

 name implies, best adapted for swimming. The figure of the breast 

 resembles that of the keel of a boat ; the body being clothed with a 

 thick plumage, tends to increase the bulk without very materially 

 augmenting the weight. The plumage is very compact, and being 

 lubricated with an oleaginous secretion, the water cannot penetrate to 

 the skin. The bones of the skeleton are extremely light, and many 

 of them are hollow, so that the specific gravity of birds is much less 

 than that of water ; indeed, were it not so, they would be utterly 

 unable to swim, and much less to fly in the rarer medium of aits The 

 specific gravity of birds is so much less than that of water, that we 

 observe, as in the Grebe, Petrel, &c. (fig. 10), that by far the greater 



Fig. 10. 



Grebe Petrel. 



portion of the body is above the water as they lie flat on its surface. 

 They require therefore no action of the limbs to sustain them on the 



Fig. 11. 



Foot of Grebe. 



