George Streynsham Master.

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would tend to diminish the vigor of such
parts of the larch as are immediately under
the influence of its dense shade. But no,
it pushes out as decidedly and strongly
in this direction as in any other. It has ev-
idendy been grafted high, some six feet, but
whence its eccentric nature is derived, who
shall say ? It does not certainly suggest the
growth of the European larch as we gener-
ally see it. Some strange abnormal form
must have been perpetuated in a very com-
plete manner by grafting. This particular
specimen is the largest we have ever seen.
The trunk is of moderate size, scarcely one
foot in diameter, but it is nevertheless at
least thirty years old.

We come now to an evergreen, which the
larch is not, though it looks like one. JPicea
Birumsi^ lasiocarpay Lawiiy and possibly
some other synonym, is a Rocky Mountain
sflver fir, a variety of P, grandiSy one of the
noblest evergreens of that region of noble
trees. The specimen delineated stands in
Flushing, on the grounds of Mrs. Leavitt,
and is the finest in every way, as we be-
lieye, in America. No comparison should,
of course, be made between it and native
^)ecimeDS. Their development and habits
are utterly different If native trees are
sometimes more picturesque, they have never
that perfection of detail exhibited by the
cultivated plant. Dififerent seedlings from
the same Parsons' silver fir present differ-
ent colors and forms, but the best forms are
marked by a strong upward curling of the
leaf. The blue, silvery lining of the lower
surface thus exposed gives a beautiful variety
to the general coloring. It will be noted
also that the symmetry of this tree is per-
fect, the branches extending regularly out
almost at right angles to the trunk. Nearly
all the beautifiil Rocky Mountain ever-
greens have been introduced within forty or
fifty years. This specimen was obtamed
from about the first lot of Picea Parsonsi seed
that produced any plants worth mentioning.



The date of its birth was nearly thirty years
ago. Yet, for the kind, it has grown well,
and is probably twenty-five feet high. Every-
thing about its appearance is solid, rich and
picturesque, the masses being peculiarly
mteresting and attractive; but the finer
forms are extremely rare, and can only be
seciu-ed satisfactorily and with certainty by
grafting with cions taken from the best trees.
Seedlings are very unreliable, and often run
into far less beautiful forms than that of the
illustration. Grafting, however, the onhr
practical method of propagating it, is dim-
cult, chiefly because little wood fit to pro-
duce fine trees can be found on any plant,
and the plants from which to cut are them-
selves scarce.

To the right of the Parsons* silver fir, in



CHINBSB CYPRBS8.



the clustered studies of specimens, is a
unique plant of the weeping Norway spruce,
Abies eoccelsa inverta, one of our best weep-
ing evergreens. It represents, perhaps, the
extreme form of the graceful that a tree can



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44



RARE LAWN^TREES.



attain without lapsing into the grotesque.
The larch just noticed is unquestionably
grotesque, but, on the other hand, the
thoroughly pendent grace of the weeping
Norway spruce has a method in its abandon
which is simply beautiful. Suggesting the
genera] habit of the Norway spruce, the
branches droop in picturesque folds, closely
enveloping the stem, and now and then
bursting forth in upward eccentric curves, as
if overflowing with vitality. This peculiar
and picturesque growth confines itself in
this case rather more to the younger and
upper part of the tree, for the reason that it
has been left without pruning and training
during its younger days. The paceful for-
mation of the weeping spruce is made still
more valuable by its perfect hardiness, fine
transplanting qualities and moderate growth.
Oiu: illustration presents a specimen about



twenty-four years old, and nine feet high.
During early life the weeping Norway spruce
is much aided in attaining its finest habit and
a definite symmetry, if it be carefully and
systematically trained to a stout stake, and
also pruned with judgment. For want of
such training many weeping evergreens, and
deciduous trees for that matter, fail to attain
the symmetry and picturesque beauty they
might otherwise have. The narrow col-
umnar beauty of the weeping Norway
spruce, as well as its moderate growth,
specially fits it for the ornamentation of
cemetery lots.

We pass on to the last and perhaps best
member of our somewhat heterogeneous
collection of distinguished lawn-trees. Yet
how can we do justice to this specimen of a
weeping beech ! The picture expresses much,
ind we may tell you it is 50 feet high and
50 feet in diameter of foliage, the largest

thic cathe-
a grove of
)t conceive



PARSONS ttlLVBR FIR, WEEPING NORWAY SPRUCE, AND WBSPING LARCH.



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Jl^XE LAirX-TREES.



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WKSnNG BBBCH.



its beauty in any adequate degree. The only
way this can be done is to stand before it
at sunset, when the noble outline cuts itself
sharply against the evening sky, and the
lights and shadows are clearly defined.



Our sense of its great size, charming as well
as imposing, increases as we gaze. Its
recesses and brighter parts become more
picturesque, and we are impressed more
and more by the beautiful eccentricity of



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46



THE MISSISSIPPI JETTIES.



growth it develops here and there, just
enough to suggest an abounding and over-
flowing affluence of health and endowment.
All tlus is kept well in hand and never
lapses into mere grotesqueness. Every one
knows what a bright, glossy surface the
beech leaf has, and can therefore perhaps
conceive how the charms of the weeping
beech are thereby enhanced. But notice
in the next illustration the anatomy of the
weeping beech in its grand winter naked-
ness. How eccentric and picturesque the
rounded solid branches and long, drooping
slender twigs! This specimen is 40 years
old, but if any one expects his specimen to
attain the same dimensions in a similar
time, he will most likely be disappointed.



This extraordinary development is very re-
markable, for the soil is not, one would
suppose, specially fitted to produce such
growth, being, except a foot or two of the
surface, quite sandy to a considerable depth.
A grand and beautiful specimen of a
choice tree should be preserved and exhib-
ited in as many ways as possible, and laws
should be made to protect it wherever its
retention does not injure the health of ad-
jacent parts. If it prove necessary, in any
case, to secure it by acquiring ownership, the
public should furnish the money for what is
really a public benefaction. Such monu-
ments of arboreal excellence should be
reckoned far more precious than imperfect
human designs wrought in stone or bronze.



THE MISSISSIPPI JETTIES.



In 1859, a committee from the New
Orleans Chamber of Commerce visited the
mouth of the Mississippi at its largest out-
let — South-west Pass, to see what detention
vessels were subjected to in passing in and



out. They found the bar block-
ed with a vessel, while fifty-five
other vessels were waiting to
come in and go out. The total
amount of freight on board the
out-going vessels was 7,367,339
pounds. Some of these vessels
had been there for weeks, waiting
for a chance to go to sea. So
common were these detentions
that the usual expression of pilots
and tow-boat men was not that
a vessel *' went to sea " on such
a day, but that " she was put on
the bar," with the understanding,
of course, that she was to be
pulled at by tow-boats for days
and perhaps weeks.

The river at the head of the

passes finds its way to the Gulf

of Mexico through three different

channels. The South-west Pass,

the broadest and deepest of them

all, trends to the right, and Pass

\ rOutre, the next in size, to the

east; while lying between these

two and more nearly in the direct

course of the river is the South

Pass. The river just before its

subdivision is one mile and

three-quarters wide, forty feet deep, and

carries every minute, when at flood, 72,-

000,000 cubic feet of water to the Gulf, or

enough to fill Broadway, New York, sixty

feet deep firom the Battery to Madison



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47



Square. Every cubic foot of this vast
volume of water contains nearly two cubic
inches of sand and mud. Enough earth
matter, it is estimated, is annually thrown
in the Gulf to build a prism one mile
square and 268 feet thick. The compar-
ative volumes of water flowing through
the three passes are approximately as fol-
lows : South-west Pass carries fifty per cent



each pass) about 1,200 or 1,500 feet wide
in the two large passes, and 600 feet wide
in the South Pass, and the depths are about
fifty feet in the large passes and thirty-five
feet in the South Pass.

The banks, although composed of the
deposits of the pass itself, — sand and clay, —
are sufficiently tenacious to confine the
water, and thus give it the requisite scouring



WORK-SHOPS, DBRIUCK, DKBOGK AND JBTTY TUG, PORT BADS, LOOKING DOWN THB PASS.




LOOKING OUT TO JBTTIBS PROM PORT EAOS.



PORT BADS PKOM WB8T JBTTY CONCRBTB WMARP.



of the whole river. Pass \ TOutre forty per
cent, and South Pass ten per cent. The
accompanying map of the delta will give
a dearer idea than any verbal description
can do of the relative positions and lengths
of the three passes. At the mouth of each
pass is a bar over which there is more or less
depth of water. At South-west Pass the depth
of water on the bar is about thirteen feet, at
Pass i rOutre it is ten feet, at South Pass,
before the construction of the jetties, it was
eight feet The crests of these bars are not
immediately at the end of the land, but
from two and a half to five miles out in the
Gulfl Through the whole length of the
passes there is a deep channel (uniform for



power to excavate and maintain a deep
channel, but as soon as this confined volume
reaches the land's end of the passes, it
spreads out instantly to the right and left,
and, losing a portion of its velocity by this
diffusion, is no longer able to carry all its
sediment, but drops it upon the submerged
banks.

The central thread of the current, how-
ever, maintains its velocity for some distance
into the Gulf, but, gradually losing it, scat-
ters its load of sand and clay over a wide
plateau. New floods coming down bring
more sediment, which is deposited further
out than that of the precedmg flood, and
thus the bars for all time are advancing



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THE MISSISSIPPI JETTIES.



with more or less rapidity into the Gulf.
At the South Pass, this advance was at
the rate of about loo feet per annum;
at the South-west Pass over 300 feet per
annum.



CAPTAIN JAMBS B. EAOS.

AVithin the conditions of the difficulty to
navigation at the mouth of the Mississippi
has been found the clue to its solution ;
for just as fast as the pass builds the bar out
into the Gulf, just so fast it excavates a
channel behind it So that at the South
Pass, for instance, while one hundred feet
was each year added to its bar, — located
two and one-quarter miles from land's end,
— it at the same time added one hundred
feet to its banks, and thus confined the
water sufficiently to deepen the new chan-
nel during the year to the same depth found
elsewhere in the pass. Captain Eads, catch-
ing this suggestion from nature, reasoned that
if he could extend the banks of the pass, not
gradually at the rate of 100 feet per annum,
as nature was doing, but immediately two
and one-quarter miles out over this bar into
the deep water of the Gulf, he would pro-
duce sufficient power to excavate not only
the 100 linear feet per annum, which nature
was doing, but the whole length of the bar
from thirty feet depth at the land's end to
^^'^irty feet in the Gulf of Mexico.



Although the bar extended out from the
end of the land two and a quarter miles,
yet the depths of water found at differ-
ent points varied greatlv. At half a
mile from the land's end, it was about
twenty feet; at one mile distance, it was
fifteen feet ; at one and three-quarter miles,
it was ten feet ; and from this point to nearly
the outer edge of the bar, it varied fix)m
eight to ten feet, with a somewhat slighter
depth at the crest of the bar. From this
point there was a comparatively rapid de-
scent into the deep water of the Gulf.

Lying in front of each of the passes,
especially those which carry the largest
amount of sediment to the Gulf, is found a
pecuHar formation called " mud lumps."
Various theories as to their origin have been
advanced. One is, that the decomposition
of organic matter brought down in the sedi-
ment of the river generates gases which
cause an upheaval, tfirowing the overlying
strata in some cases out of the water, to a
height often or fifteen feet. Another theory
is, fiiat the pressure of the superincumbent
mass of the deposits on the landward
side of the crest of the bar, forces up these
ridges and lumps which lie in the softer ma-
terial outside, and in the line of the least
resistance.

There are some phenomena connected
with the tides and the Gulf which deserve
mention, for they exert a very important
influence, not only upon the channel
between the jetties, but upon the Gulf
bottom beyond. For about 250 miles along
this coast, the tides are diurnal — a phe-
nomenon to be found nowhere eke. Their
average rise and fall is only about fourteen
inches, though, of course, extraordinary
storms and unusual conditions of other
kinds will produce a greater range. The
winds, which during the fall of the year
have very much the character of trade winds,
blowing from the north-east, affect the cur-
rents of the Gulf so that there is at times a
current of from one to two miles an hour
flowing to the westward. At other seasons
of the year, when the wind is from the west-
ward, there is a decided current setting
to the east. During seasons of calm weather,
however, no perceptible current exists. It
has been suggested with some reason, that
the water along the shore of the delta is
influenced more or less by an eddy of the
Gulf stream. The in-coming and out-going
tides which, according to the investigations
of the United States Coast Survey, ap-
proach the delta from the south-east, are



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THE MISSISSIPPI JETTIES.



49



also another cause of a current sweeping
past the mouth of the river. The storms of
the Gulf, especially in the fall of the year, at
times cause extraordinary currents. It will
be noticed by an examination of any map of
the United States, that the mouths of the
river are thrown out about loo miles from
the main shore line of the Gulf. They are
themselves huge dykes built out into the
currents and counter-currents of tiie Gulf.

Having thus briefly described the mouth
of the river and its bars, let us see how
great an obstacle they have hitherto been to
the development of the Mississippi valley.

The Mississippi River may be justly con-
sidered as the tiade outlet of a vast empire.
The tributary region, having an area of one
and a quarter millions of square miles, is more
than equal to the whole extent of Europe, leav-
ing out Russia, Norway and Sweden. This
area has a population of at least twenty mill-
ions, and produces yearly about one billion
bushels of cereals, two million bales of cot-
ton, and two hundred thousand hogsheads
of sugar. A large part of this agricultural
district is so far distant from the markets of
the eastern sea-board, that its products do
not prove profitable if transported by rail.

The development of the valley resulted



rOutre. At one time provisional jetties were
attempted, but the project was abandoned
for want of means. Expensive dredge-boats
were constructed by the government to work
on the bar, at an annual cost of about $250,-
000, and according to the report of a board
of United States engineers, there was in 1872
and 1873 a depth of from thirteen to twenty
feet on the South-west Pass bar, but the hope
was not encouraged that a channel could be
maintained of more than eighteen feet depth.

Meanwhile, the tonnage of vessels import-
ing and exporting between the eastern sea-
board of this country and foreign ports, had
largely increased, so that a ship of from 1,200
to 1,800 tons burden was the ordinary size;
yet the average size of vessels entering the
port of New Orleans, prior to the opening
of the mouth of the river by jetties, was
not over 700 tons. During all the previous
years, both before and after the attempts to
open it by dredging and other means, it was
the exception rather than the rule, for a
loaded vessel to pass over the bar without
detention.

This was the condition of the bar, and
such were the obstructions to commerce,
when, in the winter of 1874, Captain James B.
Eads appeared before Congress and oflfered



Bm/S-KYB VIKW OP THE JBTTIRS. (THE NUMBERS REFER TO THE DEPTH OP FEET IN THE NEW CHANNEL.)



from time to time in the improvement of the
river and its tributaries. Since 1839, eflforts
have been made to deepen the channel at
the bars of South-west Pass and Pass i
Vol. XIX.— 4.



to open Uie mouth of the river by jetties,
stipulating that he should take no remunera-
tion for his work until a channel from the deep
water of the pass to the deep water of the



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THE MISSISSIPPI JETTIES.



Gulf had been secured. The maximum
depth to be obtained was thirty feet; and
neither that nor the intermediate depths was
to be paid for until the work was complete.
Although offering to do this work at his
own risk and expense, he met with a most
determined opposition, both from govern-
ment engineers and from the very section of
the country which would be most largely
benefited by a deep channel to the Gulf.
The people seemed to have become in-
doctrinated with the belief that an expensive
canal, and not an open river mouth was the
best solution of the problem.

Captain Eads and his opponents before
Congress held views diametrically opposed
to each other. General Humphreys, the
chief of engineers, in published pamphlets,
and, moreover, in statements before the
Congressional committees, contended that
it would not only be impossible to build
jetties and maintain them, for various rea-
sons, on account of the unstable nature
of the foimdation on which they would rest,
the undermining action of the river currents
and the violence of the storm waves ; but
that, even if these were constructed and
maintained, the bar would advance so much
more rapidly than before, that the jetties
would need to be extended 600 feet every
year to keep pace with this accelerated ad-
vance. Captain Eads contended that the
river is a transporter of solid matter to the sea ;
that the amount transported depends upon its
velocity modified by the depth of the water;
that this principle determines the channel
and the bars ; that, if the banks of the pass
were extended in parallel lines as they are
by nature, the result would be an increased
velocity, and this increased velocity would
enable the river to pick up the particles
of which the bar is composed, and carry
them far out to sea, where under the influ-
ence of the Gulf currents they would be
swept away; that as the crest of the bar
was two and a quarter miles from the land's
end, the crest of the new bar when formed
could not possibly be nearer than two and
a quarter miles from the end of the jetties,
and that probably under the new conditions
the formation of another bar would not
take place for a century or two.

These views were so clearly and forcibly
explained to members of Congress, that,
in March, 1875, a bill was passed by which
Captain Eads and his associates were author-
ized to construct and maintain jetties and
auxiliary works for deepening the bar at the
«inuth of South Pa.ss between the pass and



the Gulf of Mexico. It was the earnest wish
of Captain Eads, — a wish which he urged in
vain to the last hour of the session of Con-
gress, — to improve the bar at the mouth of
South-west Pass, because the greater depth
and width of that pass afforded an entirely
unobstructed outlet for the commerce of the
valley, and one able to meet its increasing
necessities. Tlie width of the channel here
through the jetties would have been 1,500
feet, while that of the South Pass is but 700
feet.

Immediately after the passage of the act,
preparations were made for beginning the
works. A contract was entered into with
Colonel James Andrews, of Alleghany, Pa.,
the successful builder of the foundations
of the St. Louis bridge. He arrived at the
mouth of South Pass about the middle of
June, 1875, bringing with him the necessary
plant and force, and began work in earnest.
By his indomitable will and untiring energy
Colonel Andrews has proved himself equal
to the task of carrying through to complete
success this great and difficult undertaking.

Let me describe the surroundings here,
as they appeared at the time of our arrival.
Qimb with me seventy-five feet to the top
of the light-house : there is no other eleva-
tion or building within ten miles; you
cast your eye over not exacdy a landscape
or a waterscape but an amphibio-scape
of water, mud, reeds and alligators, — not an
elevation as far as the eye or glass can
reach that one could not easily leap over,
except a solitary mud-lump lying oflf
to the westward; an unbroken horizon of
sky and water on every side. Fourteen
and a half miles to the east lies the low
green bank of Pass k TOutre; as many
miles to the west is the dim horizon line of
the South-west Pass. A light-house stands
at the mouth of each of these passes, and
ten miles away to the north-west is barely
distinguishable another, which marks the
head of the passes. Half-way up the South
Pass we see Bayou Grande diverging and
flowing to the westward, carrying off" about
twenty-seven per cent of its waters ; while
everywhere from the north-east to the south-
west the rolling waters of the Gulf of Mexico
stretch to the horizon. This beautiful ship-
canal, South Pass, though small when com-
pared with the other outlets, is large enough
to meet any present or future need.

The jetties, let it be understood, are in-
tended simply as a nucleus around and upon
which Nature can build her banks, and so,
some of the work, since it was to be solid-



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ified by the processes of nature, has been
of a comparatively imperfect character.
A glance at the sketch giving a " bird*s-eye
view of the jetties" will show their general
position in reference to the shore lines.
Several objects were sought in their loca-
tion:

I St. To lay them out in such a direction
that they should be both parallel with the
river currents, and, where they project into
the Gulf, at right angles to the currents that
sweep along the shore.

2d. To place them as far apart as was
possible consistently with the necessary
concentration of the volume of water, and
at the same time to remove the jetties them-
selves from the undermining action of the
river currents.

The jetty hnes were marked out first on
paper, and then at times with considerable
difficulty on the bar. It will be seen that
there were no landmarks near the line of the
jetties from which measurements could be
taken to locate the guide- piling. Here and
there, perhaps a mile or more apart, were
temporary stations or tripods marking tri-
angulated points, which had been estab-
lished during the preceding winter by the
United States Coast Survey. From these,
by careful calculations and instrumental
work, the jetty lines were laid out in an
easy curve, extending from land's end on
the east to a point two and a quarter miles
out in the Gulf.

The piling which marked the jetty lines
was driven in various depths of water from
four to thirty feet, and the foundation,
which it had been prophesied would prove
so unstable, was found to be so solid that a
hammer weighing 3,000 pounds and falling
nineteen feet could not with eighty blows
force the pile more than seventeen feet into
the bottom.

The jetries are constructed principally of
willows. These trees grow in great abun-
dance about twenty-five miles up the river,
and vary in size from one to two and a



Online LibraryGeorge Streynsham MasterThe Century, Volume 19 → online text (page 8 of 160)