The republic. [volume] (Washington [D.C.]) 1849-1853, 1852-11-02
From the Springfield Bfass.) Republican.
Ar.tmrnual EOllRRo,

From the Springfield (Dfass.) Republican.
Autumnal Foliage.
The beautiful appearance of the autumnai foil
age, which this year seems almost TO surpass In
gorgeousness that of any previous season. often IN
duces an inquiry as TO the reason Oh tne cnange
which few frosty nights make in the green livery
Of our trees and forests. The question 10 purely a
chemical one, and one, moreover, about whicn
there il no very general agreement OF opinion. In
facts there is no subject included among ns'a ara;
change in the constitution or arrangement OF mat
ter whereby particular body is caused to reflect
or absorb light in such way that It assumes AZ
one time wholly different color; Ihese changes
are very far from being confined to any one spe-
cies of matter. The trout, which, on sandy DOT
tom, has a yellow, speckled hue, becomes dark
brown or blue beneath shaded bank; the yellow
of the weasel and the rabbit, maintained during
the summer months, is already changing to white;
aud il s susceptible of rigid demonstration tnat tne
blue of the October sky is not the same, either IN
tint or quality, with that which welcomed tne
bursting of the leaf in the months OF April OF way
The general supposition in regard to the change
of the leaves 10 this When TIE tree or plant Is IN
full activity its foliage, it is well known, absorbs
carbonic acid and disengages oxygen. When'
now, through the influence OF suncieht'y low
Temperature, or from any other cause, the Iunc-
tons of vegetable life suspended, and the hulds
cease TO circulate, the leaves no longer
oxygen, but, in common with all dead bodies ab
sorb this gas, which, forming an acia, changes .ne
colors of leaves either to yellow, red, or some
intermediate shade, depending on the quality Of
the matter present in the leaves II has also been
asserted that this acid can be neutralized by an
alka and the green restored h not rss NOW Nv
any re- agent; but when it has become red 80
luton of potash will change 1t to green, because
the red coloring matter forms green compounds
with that akah. a..E 81, ssta
Rer.eus. ths ereat Swedjsh chemist, spent con-
adorable time in investigating this subject. He
found that when the yellow leaves were treated
with alcohol, they yielded a granular substance,
which had tendency TO orystaHsation, ano also s
iical with the grains. These contained the yellow
colorinR matter OF the leaves, which Is described
as yellow, fatty, unctious substance, easily melt
ed and on cooling becoming concrete ano d "a amr
exposed to the air and light 1t loses its color en-
tirely Berzelius of the opinion that the trans.
formation of the green colorng matter OF the ieaf
into yellow IL effected 5y IhsGgsi IN me E orgaaf
fort to reproduce the green from the yellow proved
fruitess; neither could he succeed in changing the
green coloring matter to yellow. The red coioring
matter of the leaves has been also extracted, and
il believed to be tho same with that of red fruits
The brown color which leaves assume when COM
pletely withered has nothing in common with
either the red or the yellow coors 1t ID produced
by an extractive principle originally coioriess' ou.
leaf structure has decayed off, is acted upon by the
oxygen Of the air, and communicates to the hbrous
skeleton of the leaft well known brown color. This
color is one of the most fixed and interchangeable
with which we are acquainted, and cannot be i'm
paired or destroyed by the most powerful chemical
re. gents This, we believe, embOdies all that is
at present known, scientifically speaking, respect
ing the change OF the Leaves. Inc dMaereht ap
ferred to difference in their nature and the dlf,
ferent changes observed in different countries and
locations is undoubtedly owing to different climatic
conditions. '-e-saF rr.'. "-E ..."a.
The HYDRAULIC RAM.-Tne hydraulic ram is a
simple mechanical apparatus, constructed upon
philosophical principles, and Is used very enecuve-
ly in raising portion of the water from spring
or running brook above the level OF its fountain
head. The following description, it is believed,
will be easily understood. Suppose water pipe
is laid along down the Of the stEea N through
which the water is required to pass. The lower
end Of the pipe is closed and near that extremity
10 an orifice the upper eide which IL opened and
closed on the inside by pupPet valve shaped
something like an inverted barrel bung. There
s also another similar orice and valve opening out
ward from the main pipe, and into an air vessel.
Now let beth valves be closed. As there is then
no means of escape for the water in the
from the spring, it is brought to state OF res IT,
gravity 10 greater than the pressure OF the water at
rest in the pipe it consequently falls into the pipe,
leaving the orifce open, through which the water
Immediately begins to rush with Increasing velo-
city, until is momentum becomes such as to push
up the valve to its place in the orihce. The
momentum OF the water suddenly stopped in its
course IL such to lift up the other valve opening
outward into the air vessel, through which the
water roshes, COMPRISING the air into q smaller
compass until the reaction Of the afr IL In equi-
iibrium with the action OF the water, when the
valve No falls back to its place and prevents the
water in the air vessel going back again into the
main pipe. The water in the main pipe then hav-
ing no escape ia again brought to rest, whereupon
valve No. falls down again by it's own weight,
and the process is again repeated. From the air
vessel dischnrging pipe leads of to the upper
story of house, or any other place where the
water is wanted to which point it is driven BY the
elasticity of the compressed air in the vessel or
course tho amount of water raised, compared to
the WHOLE will be in inverse ratio to the elevation
OF the discharging point above the fountain. head.
The momentum Of the blow forcing the water into
the air vessel when the valve closes, was well IL
Illustrated at the time the fountain was fret put in
action on Boston Common, WHERE it will be recol-
iected, the momentum of the water was great,
at the sudden stoppage of the Jet, to burst the
pipes and deiuge tho Common.-Boston Journal.