Burlington weekly free press. [volume] (Burlington, Vt.) 1866-1928, 1911-11-23
TO-MORROW'S FOOD
Will Man Ever Learn to Make 1t
Instead of Growing 1t?
a Time Coming when Population May
E,recJ Earth's Powers of Feeding
It-s,nthetic Foods viii Then
He in Order.

In thc attempts to forecast the future
ropulations Of countries and continents
the statistlcian ha. sometimes SGT against
calculations based on the normal or ar
ferentia rates of Increase, the check
afforded by the supply OF food, SAYS the
London Morning Post Populations can
not Increase beyond the point AT which
thcer is enough TO feed them; and unless
| man possesses enough adaptahitv to cat
| the synthetic proteds which science may
succeed in making for him, we should be
| inclined to say that his numbers mus. be
| limited by the amount Of ground that can
| be brought under cultivation. and the
amount OF sea on which his fisheries can
levy a contribution. But the calculations
| OF the periods at which wheat tor coan
| or any other Of mans necessities will fail
| have hitherto proved rather unsatisfac-
, tory, and have been continually subject
| to revision as new sources of supply have
| been discovered If that were not so the
world, according to a very careful esti-
mate made in 1S}S would begin to starve
in 1881. Is there any basis for computing
| the limits OF productiveness? Or w. ].
McGee in examining the widely differing
| estimates of the ultimate population of
! tine United states, which the latest COM
| puter, Henry Gannett. puts at 10000 900
ninety years hence-points out that a
practical limit to the productivity and
| tabituaity Of a country lie fixed by limi-
tation in It's water supply. In arid lands
| like Egypt careful calculations have been
made of the amount of water necessary
| to make land productive. An acre re-
quires so many inches Of water year.
let us say thirty, before it will raise
enough vegetable food TO keep one per.
son. Thirty inches IS under the mark
because man does not live by bread alone
| but on meat. and the animals which give
him that have also to be sustained by
vegetable food. The man who eats 200
pounds Of bread and 200 pounds Of beef a
year drinks in the same time a ton Of
water. and the equivalent OF 400 tons of
water which have gone to make the
bread, and 1000 tons of water which have
gone TO rear the beef-4,4Q0 tons of water
In all Consequently the water supply of
a country in which man is TO live must
be always equal to something over 1000
tons per Individual. The annual rainfall
OF the countries OF the northern hemi-
sphere is about thirty inches. only half
enough TO fertilize one acre to sufficient
extent 10 keep a man. Roundiv speaking.
| perhaps one might say that the world 5
water supply is sufficient to keep pop
ulat.on of one man to every two acres.
| A mile below the surface Of the sea no
! light penetrates; the darkness IS more in
tense than that OF the darkest night at
100 metres the ultraviolet rays, which
| the eye does not perceive would be per-
ceptble to q Photographic plate, at half
that distance the red rays cease, though
the blue and violet still penetrate. In the
Investigations which DR.. Hart has made
In the North Atlantic he has found tina,
below th.s 5o0-instre4evel the fishes taken
the surface the fishes begin to have larger
eyes ana silvery sides Tie inference is
that the region which the red rays OF
sunlight penetrate, and the darker re
gion 10 which they cannot reach. are
characterized Ivy differently colored kinds
OF fishes. and that the difference Of color
arises possibly from the amount of ligh'
they receive. possibly ae the result OF ar
attempt at protective coloration. Some
interesting observations on the theory
have been furnished by DR.. c. V. Burke
who has been doing similar work in thu
Pacific though combining his attention tC
one species of marine life. In a region OF
total darkness, he points out. the color O
an animal could not be an aid to coucca!
ment IT might Just as well be brilliantly
colored as transparent or black. Blu
there IL no denying that the coloratioi
appears TO depend on the amount o
sunlight TO which the species are sub
jected. There are two possible sources o
light in the oceanic depths below thu
penetration OF sunlight Certain anima.
Of this region have light reproducing or
gans and decomposing animal matter al
so may give forth a phosphorescent glow
And, a 5 If for the purposes OF sight in
dim light. the eyes OF the fishes have be
come greatly enlarged. Contrast nov
the effects of darkness IN cave fishes
These do not need protective color 70
. there are no enemies to be protecte'
from They lose their pigment, becom
paley white and their eyes become afro
phed The ocean fishes surrounded b.
! other fishes with large eyes and hostil
teeth, acquire pigment and become who'll
black, Possibly the effect of the rays o
! light Ii the warp and the struggle 70
( life the woof of the cooration of fishes.
8 Those OF us who have reached what
novelist lately called the prime Of earl
middle age may have remarked during GA
holidays noticeable quetude in the bat
that wheel overhead at shutdown. Close
observation may have disclosed tho fac
that while the rustic Of their leather
wings could he detected as they flew by
yet the shrill squeak so characteristics O
, the bat was absent. The reason wa
= TO be sought in our own ears. The hear
ing OF many persons, while remaining al
| parently as capable as ever of notn
q light sounds, becomes after forty or eve
l earlier unable TO detect very high pitche
; sounds, that Is to say, sounds which ar
produced by very rapid vibrations. TIL
human ear. at its best, can hear sound
$ which range from thirty or forty vibrf
. lions "A second 0he lowest musical note
TO thirty-eight thousand vibrations a seC
q ond But many persons with averaE
Il powers OF hearing are deaf to vibration
I OF thirteen thousand a second Old pee
g pie often lack the ability to distinguls
T the letter IS" distinctly The reason
that the kissing sound when analyse
u into (sound) "wave form" is n succe'
: sion OF waves with minute irregularitiC
u on the face OF the waves; and thus f,
the purposes of implying on the ear b,
comes equivalent to a sound OF very hig
pitch Campbell and Dye have late
published an account OF some work q
the detection of sounds ordinarily ina,
= | dible, such sounds probably occur