928 CONCLUSIONS. 
and when his head and tail were on parallel lines they appeared 
not more than two or three yards apart’ (44), — “he turned 
slowly, and took up considerable room in doing it” (69), — “it 
turned with considerable noise” (117). 
When the animal swims, either with vertical undulations, or 
with its body in a straight line, holding, however, its head just 
at water-level, so that the nostrils are only above the surface to 
breathe, it generally shows nearly its whole length, only the very. 
end of its tail being under water. In such a condition it must 
swim very easily, for the water carries its total weight, so that it 
is actually null, and the animal in swimming has only to surmount 
the friction and the resistence of the water made against an object 
in motion. But as soon as the head 1s lifted above the surface, 
the weight of it must immediately be carried by the body. It is 
therefore not astonishing if an observer states: “its progressive 
motion under water was rapid; when the head was above water, 
its motion was not near so quick” (31), “when immersed in the 
water his speed was greater” (41). It is very natural too, that 
when the head is held above water, and when consequently the 
body must carry the weight of the head, the body sinks a little 
deeper into the water: “his head was now more elevated above 
the water, and his body more depressed below’ (51), and that 
when the animal has raised its whole neck quite erect in the air, 
the body has sunk so deep that it is: “not visible at all” (149), 
and that “the disturbance on the surface was too slight to attract 
notice’ (149). Therefore figg. 33, 34, 35, 37, 38, 46, 48 and 49, 
are tolerably well delineated. Fig. 33 shows us the animal swim- 
ming with vertical undulations, holding its head on the level of 
the water, and having nearly its whole length visible on the surface. 
In fig. 34 the head is held a little above the surface, and the 
end of the tail is already below it. Fig. 35 shows the head still 
more elevated while of the tail nothing more is visible. Figg. 37 
and 88 represent the animal floating on the surface, showing the 
ridge of its whole back. In figg. 46, 48 and 49 the animal’s neck 
is elevated as high as possible, but its body is of course too deep 
to be seen. 
A few lines above we have spoken of the increased speed of the 
animal swimming under water. The question arises how was this 
to be seen; and the answer is given by the eye-witnesses themsel- 
ves: “I saw it coming rapidly under water’ (31), “when moving 
under water you could often trace him by the motion of the water 
