Evening star. [volume] (Washington, D.C.) 1854-1972, 1904-12-10

Here We find the largest plants known in
nature, at least so far as length is con-
cerned. Pacific coast form being unques-
tionably from seven hundred to eight nun
dred feet in length, while others have been
reported from twelve hundred to fifteen
hundred feet long. The algae also include
the largest single-eelled plants at present
recognized, some of the tubular forms often
extending for several feet without q dis
tinct cross-wall, while others Chose Of Iso-
diametric shape) are as large as golf
ball. Familiar salt water algae ale the
brown Helps and wracks so common along
the northern coast, as well the smaller.
more delicate red forms which have been
so popular in the adornment OF Christmas
cards, calendars, etc.
There are hundreds of species of fresh
water algae, but only about dozen Va-je-
ties which give trouble in our water sup
ply reservoirs. The thick, spongy layer
that gathers on stagnant pools and is popu-
larly called frog spawn or pond scum is one
kind Of algae. but, as a. rule, the algae
which cause the bad taste and smell OF
water supply systems are the minute Al
almost invisible FORMS of which perhaps
the best known are the blue-green algae.
Though the individual plants are invisible
TO the naked eye, there are so many tnou-
sands of them In each cubic centimeter OF
water in polluted reservoir Gas many as
$1,000 TO the cubic centimeter have been
counted) that the water has n greenisn,
Shiny look and gives everything a disa-
greeable green stain. Each tiny organism
when this oil is liberated by the death ana
decay of the cell, or the breaking Of the
oil sacs, the stencil begins. The usual color
of the algae is blue-green but ii may he
olive. yellow and brown. chocolate or pur-
plish red. Algae are of very simple struc-
ture and of many designs, varying from
wheel to glass marble or a necklace.
Some of the designs are beautiful when
magnIfed three hundred or five hundred
times.
Poison for the Plant.
Dr. Moore obtained specimens of algae
from all parts of the country and in MS
laboratory tried the effects of different
substances on them. His aim was ID dis
cover a substance that would poison the
algae and yet that would not harm the
water and that would be cheap. Free
chlorin and sulphur dioxid at dilutions or
/ to 1000 or 10000 destroy many forms or
algae but both substances are very injuri-
Gus to animal life. Silver is exceedingly
effective. but its cost is prohibitive. Mer-
curry and lead are, of course, out OF the
question, and zinc requires too high con-
centration to be practicable. 1t is not nee
essary to describe in detail the many snb-
stances tried and found wanting. Suf-
flee IT to say that DR.. Moore found that
copper sulphate. Familiarity known as blue
vitriol, possessed exactly the virtues he te-
quired. Tests showed that very little or
this substance will destroy all algae organ
absolutely prevent their recurrence; it dis
solves so easily and thoroughly in water
that every bit of the copper which does the
poisoning is freed to act Immediately.
This compound proved, in fact, such
willing and facile distributor of the copper,
weak solutions as / part of copper 10 IT,
O00 600 or 10000, 900 parts of water beng
powerful enough to kill most of the algae
FORMS that DR.. Moore thought IT might be
used to relieve the farmers of Virginia and
other southern states who are complaining
that their beds of water cress were being
smothered by species of algae. The cress
sells in winter for from SO to $50 barrel,
and formerly had been profitable crop
BY dissoving small quantities of copper
sulphate among the cress beds-1 part cop
per to 100000 parts water-he poisoned
the algae weeds and brought about their
complete disappearance. But the cress was
unharmed BY one of the mysterious con-
ditiCns of nature the copper, spreading
through the water, attacked and destroyed
one vegetable organism, the algae but was
powerless to affect another vegetable or
ganism, the cress.