The Charleston daily news. [volume] (Charleston, S.C.) 1865-1873, 1870-04-14
PROFESSOR sHEpARD,s LECTURE.
''soils, their Origin, Physical and
Chemical Properties"

The second Of the course OF lectures by Fro
fessor Charles u Shepard Jr., before the Charles
ton County Agricultural and Horticultural Socle-
ty was delivered in the laboratory of the Medical
College last night There was good attendance.
Among those present were several scientific gen.
tlemen, and number of our fertiiizns mer-
chants.
The subject Tor the evening was "Soiis, their
Origin, Physical anu Chemical Properties The
speaker divided his subject as follows: Nitrogen
of the air and soil, humc substances, sulphurlc
acid, phosphoric acid silicic acid, bases, lorna
tlon OF soils, composition and properties, original
analysis The lecture was very interesting and
Instructive and we regret our inability to give
more than the following brief synopsis, which We
fear does not do the lecturer justice.
SITRoGENoUs FOOD OF PLANTS
The lecturer first treated OF nitrogcnous
food of plants, which is nitric acid and ammonia,
which are contained in all natural waters
furthermore in rain, snow, dew and mist
Although they are present in small quantities in
rain, snow and Gew, Still the amount OF nitrogen
GUS matter deposited on the soil In this manner
Is very considerable. Careful experiments car
red on at the different German agricultural
stations, have demonstrated that the amount OF
nitrogen which Is thus yearly deposited varies
from two to eighteen pounds per acre. Which VIII
be equivalent to from twelve to one hundred
pounds of Peruvian guano to the acre. Nitrogen
enters largely into the composition and food OF
ali organic structures-both vegetable and ami
NAL; hence all fallings and droppings, whether
from plant or animal, all refuse organic matter
as well as lhe decaying organic tissues, furnish
large quantities Of nitrogelous matter to the SOIL
hUMUS.
The lecturer then explained that the term hu-
mus implied organic matter undergoing and still
capable OF decomposition. Humus presents to
the plant an easy source Of food. 1t improves the
earth by the lively chemical action which 1t In
duces also by tearing up and loosening the struc-
ture Of soils, as well as increasing their power OF
retenioD and absorption OF vegetable food.
PHosPHoRIc ACID
was the next head treated Of by tho lecturer. Ho
stated that during the past few weeks there had
been discovered in the nodular phosphate depo'
sits found in South Carolina, portions OF the teeth
and skeletons OF various tropical animals sucn as
the tapir and mannite or sea-cow. With such
facts at his disposal the geoogiSt can assert that
at the period OF the formation OF this deposit the
climate must have been similar to that OF the
tropical regions Of our own time. This supports
certainly the theory advanced by DR.. c. D. Shep-
ard Sr., who Is OF the opinion that the deposit Is
In the main due to the extensive deposition OF
bird guano in this ncighborhood similar 10 that
which is still going on in the Caribbean Sea, anu
other locali ties in the tropics. The absence Oh
bird bones presents no serious objection, since
we know how easily such bones decompose and
disappear. Allowing for the action OF heat and
water upon a guano dcposk, we should expect
material similar TO that we really have IN our own
deposits. That q large number OF animal re-
mains, both marine and land, are found mixed III
with the nodules, III fact, sometimes inoedded in
them, is another proof that our continent has
been successfully raised and depressed from its
present level.
That there is wealth in our deposits need hard
ly be mentioned, bat the following facts may he
adduced to show the importance OF phosphOric
acid. The Chester cheeses OF England are Justly
celebrated, and since centuries the expectation
OF the article has been immense. Now cheese
contains over ive.per cent. of ash, or non-vola-
tile Ingredients, and prominent among them Is
phosphoric acid. This extraction OF phosphorlc
acid from the land, carried on for years, caused
partial exhaustion OF that substance. Diseases
became prevalent, which were directly brought !
about by the want OF this acid for the proper
formation OF bones in animals. To supply The
desderatum bones were collected, ground and
scattered on the fields. The supply OF bones fail
ing recourse was made to the bones OF the fallen
heroes OF Waterloo. They were disinterred aud
restored to =" soil Of Id England. Again, such
is the demau, .or phosphoric acid that the man
Of commerce actually invades the silent tombs of
Egypt in bis search for plant food.
POTASH.
The salt mines OF. Staasfurt, Prussia, afford
yearly, said the speaker, about two hundred
thousand tons Of potash salts. The deposits are
supposed to have been formed by the evapora-
ton of the waters OF q soil aboundinS In saline |
efllorescences trip through the mines Is
most delightful and instructive. When the 'isi- |
tor passes through the long galleries and cham
bers lit up by lamps and torches OF the party, lie
Is Instantly struck with the great beauty OF the
highly coored strata. One secs thick deposits of
the red, yellow and white chrystalline masses, |
lying one upon the cthel. all sparkling under the
artificial light Stassfurt In 1860, was poor,
tion other than mindlng their nocks and herds,
and tiling the worthless soil OF the neighboring |
Country. To-day, many hundred men are en- !
ployed in the mines, and In the twenty large
busy factories which have been bulk about the
village.
HOW SOILS ARE F0RaED
Said the speaker, all rock, whether volcanic or |
secondary, exposed to the influence Of moisture, |
the variations OF temperature and the atmosphcr
c air, becomes gradually dccomposed and falls 70 |
pieces. The formation Of soil BY the action OF |
cunning wafer is best observed at the mout. Of
rivers, where, owing to the decreased strength Of
the current, the particles which had been borne |
along with the stream are deposited. Occasional |
ly, where the current Of the river is sluggish, a |
large deposit OF mud and clay is formed This Is
remarkably the case III the Nile. Since our mod
ern times, the surface OF lower Egypt has been
raised from this cause III least six lec and eight
cen feet since the founding OF Thebes. The roots |
Of the plant searching after food, often find their
food locked up in strong chemical combination |
The rootet penetrates the spertures, sucks up
what it can find IN an assimilable form, and gath
ering strength, attaches ITSELF to the firm rock
tearing apart the chemical union. Direct expert |
ment has shown that the rootct OF plant grow
ing in solution deficient in lime can, In It's search
after calcareous food, attack and actually cat into
q surface OF polished marble. It IS most likely
that the rootlets OF the plant do secretc In such
cases fluids which can decOmpose even granite