OBSERVATION OF NATURE. 13 
I desire to promote, and, next to moral and religious doctrine, 
I know no more important practical lessons in this earthly life 
of ours—which, to the wise man, is a school from the cradle to 
the grave—than those relating to the employment of the sense 
of vision in the study of nature. 
The pursuit of physical geography, embracing actual observa- 
tion of terrestrial surface, affords to the eye the best general train- 
ing that is accessible to all. The majority of even cultivated men 
have not the time and means of acquiring anything beyond a 
very superficial acquaintance with any branch of physical know- 
ledge. Natural science has become so vastly extended, its re- 
corded facts and its unanswered questions so immensely multi- 
plied, that every strictly scientific man must be a specialist, and 
confine the researches of a whole life within a comparatively 
narrow circle. The study I am recommending, in the view I pro- 
should go streighte. Surely if he considered the nature of a man’s eye he 
would not wonder at it: for this I am certaine of, that no servaunt to his 
maister, no childe to his father, is so obedient, as every joynte and peece of 
the bodye is to do whatsover the eye biddes,”—RoGER Ascuam, Toxophilus, 
Book ii. 
In shooting the tortoises of the Amazon and its tributaries, the Indians use 
an arrow with a long twine and a float attached to it. Avé-Lallemant (Die 
Benutzung der Palmen am Amazonenstrom, p. 32) thus describes their mode of 
aiming: ‘‘ As the arrow, if aimed directly at the floating tortoise, would strike 
it at a small angle and glance from its flat and wet shell, the archers have a 
peculiar method of shooting. They are able to calculate exactly their own 
muscular effort, the velocity of the stream, the distance and size of the tor- 
toise, and they shoot the arrow directly up into the air, so that it falls almost 
vertically upon the shell of the tortoise, and sticks in it.” Analogous calcula- 
tions—if such physico-mental operations can properly be so called—are made 
in the use of other missiles; for no projectile flies in a right line to its mark. 
But the exact training of the eye lies at the bottom of them all, and marks- 
manship depends almost wholly upon the power of that organ, whose direc- 
tions the blind muscles implicitly follow. Savages accustomed only to the 
use of the bow become good shots with firearms after very little practice. 
It is perhaps not out of place to observe here that our English word aim 
comes from the Latin estimo, I calculate or estimate. See WEDGWwooD’s Dic- 
tionary of English Etymology, and the note to the American edition, under 
Aim. 
Another proof of the control of the limbs by the eye has been observed in 
