Alexandria gazette. [volume] (Alexandria, D.C.) 1834-1974, 1876-08-18

Among the most popular of Prof. Tyndalps
dissertations is his history of drop OF water.
H., traces it as it is lifted by the suo's heat
from the surface Of the sea; carried aloit as an
inv,sibje yapor; waited over the land; cooled by
and prccipltated upon some mountain peak,
possIbiy 10 the snow and ice OF glacier, or per-
haps sinking below the surface as rain, and re.
anpearing 10 the spring that bubbles up 10 a
valley; and at last, through rill and rivulet aud
river, 6udng its way back to ocean again.
Something like this has been done for other
substances thao water, by Prot. Pumpelly, 10 a
discou,s 80 before the NauoDal Academy Of Sci
enccs 1t has lopg been recognized that all the
materials Of which the earth is formed, are 10
course Of being gradually washed into the sea.
Modern discovery has thrown much light on
the processes by which they are transformed
into the rocks aud minerals OF good dry land
again The cycle of these changes IS, OF course,
enormously greater than that which Prot. Typ-
dali described. 1t requires eras OF time 10
which mountains must wear away and ocean
floors rise 20 the surface; compared with which
the whule kuowu history Of the human race is
an affair OF yesterday. But though SO slow, it
is contiuuvus, aud is going on at this hour all
over the globe, just as it has been ever since
there was any land lifted above the waters.
II that excellent lady of science, Mrs. Mary
Somerville, was still living. she might add
notable chapter to her instances Of the connec-
ton of the physical sciences. The geoogist,
dealing with the formation OF dead matter
rocks and stones and dry land-ls suddenly
furnished with answers to his problems by stu
dents of natural history, who are busy with anl.
ulaIs aud planets living 10 the sea. The chem
Its too, have helped largely in the research; 1t
- tln fn rnt f..f
of the story without their aid. They have
f, found md iu the ashes Of sea plants and ami.
mails, not only the alkaline earths, but the
heavy metals, lead, "copper" zinc, iron, and even
silver. These were secretcd by the vital pro-
cesses. Eveotually, when the plants aud anl-
mails are dead, they fall on the oceans floor.
The naturallsts have ascertal0rd, to some ex-
tent, what vast quantities OF these plants and
animals are concentrated in quiet eddes Oft
the edges OF ocean currents. ln some future |
age, when the sea bottom OF those localities |
shall have become hard rock and dry land,
another Comstock lode may be found where !
the precious metals have thus been slowly |
parucrcd tiom the sea. Ooe of the most Gu
rious results Of these Investigations Is the
theory that man s work ln mining and burnlog |
coal so far from deranging the scheme OF na- |
lure, will help 10 the preservation OF lite upon |
earth 1t appears that carbon is, when de- |
posted 10 the form OF coal, too slowly y soluble |
by the winds and rain to be restored in time TO
the air and sea. ln the course OF untold ages
slnce the frSl cretsce0us seas were formed, this
carbon had been quietly tucked away under
ground The plants of the sea and land were
beginning to need it. If the plants could not
live, all animals must die. The only way to
bring the carbon 10 the plants is TO convert it
into carbouic acid, and spread that in the air,
where forest leaves can decompose it, or rain ;
drops can carry it down to the weeds Of the
sea. Man digging the coal from the mine,
and burning it under steam boilers aud on the
domestic hearth, is really restoring the lost
balance to natures work. The coiers OF Fog
land and Pennsylvania are helping to prolong
the existence of every creature on the globe.
1t is very comforting doctrine to the apostles
Of labor, however it may stand the further
Tests of science