Scientific American Supplement No. 360, November 25, 1882
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Various >> Scientific American Supplement No. 360, November 25, 1882
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[Illustration]
It is, of course, unnecessary to make this correction at the time of
observation, for the angle between any terrestrial object and the star
may be read and the correction for the azimuth of the star applied at
the surveyor's convenience. It is always well to check the accuracy of
the work by an observation upon the other elongation before putting in
permanent meridian marks, and care should be taken that they are not
placed near any local attractions. The meridian having been established,
the magnetic variation or declination may readily be found by setting
an instrument on the meridian and noting its bearing as given by the
needle. If, for example, it should be north 5 deg. _east_, the variation is
west, because the north end of the needle is _west_ of the meridian, and
_vice versa_.
_Local time_ may also be readily found by observing the instant when the
sun's center[1] crosses the line, and correcting it for the equation of
time as given above--the result is the true or mean solar time. This,
compared with the clock, will show the error of the latter, and by
taking the difference between the local lime of this and any other
place, the difference of longitude is determined in hours, which can
readily be reduced to degrees by multiplying by fifteen, as 1 h. = 15 deg..
[Footnote 1: To obtain this time by observation, note the instant of
first contact of the sun's limb, and also of last contact of same, and
take the mean.]
APPROXIMATE EQUATION OF TIME.
_______________________
| | |
| Date. | Minutes. |
|__________|____________|
| | |
| Jan. 1 | 4 |
| 3 | 5 |
| 5 | 6 |
| 7 | 7 |
| 9 | 8 |
| 12 | 9 |
| 15 | 10 |
| 18 | 11 |
| 21 | 12 |
| 25 | 13 |
| 31 | 14 |
| Feb. 10 | 15 |
| 21 | 14 | Clock
| 27 | 13 | faster
| M'ch 4 | 12 | than
| 8 | 11 | sun.
| 12 | 10 |
| 15 | 9 |
| 19 | 8 |
| 22 | 7 |
| 25 | 6 |
| 28 | 5 |
| April 1 | 4 |
| 4 | 3 |
| 7 | 2 |
| 11 | 1 |
| 15 | 0 |
| |------------|
| 19 | 1 |
| 24 | 2 |
| 30 | 3 |
| May 13 | 4 | Clock
| 29 | 3 | slower.
| June 5 | 2 |
| 10 | 1 |
| 15 | 0 |
| |------------|
| 20 | 1 |
| 25 | 2 |
| 29 | 3 |
| July 5 | 4 |
| 11 | 5 |
| 28 | 6 | Clock
| Aug. 9 | 5 | faster.
| 15 | 4 |
| 20 | 3 |
| 24 | 2 |
| 28 | 1 |
| 31 | 0 |
| |------------|
| Sept. 3 | 1 |
| 6 | 2 |
| 9 | 3 |
| 12 | 4 |
| 15 | 5 |
| 18 | 6 |
| 21 | 7 |
| 24 | 8 |
| 27 | 9 |
| 30 | 10 |
| Oct. 3 | 11 |
| 6 | 12 |
| 10 | 13 |
| 14 | 14 |
| 19 | 15 |
| 27 | 16 | Clock
| Nov. 15 | 15 | slower.
| 20 | 14 |
| 24 | 13 |
| 27 | 12 |
| 30 | 11 |
| Dec. 2 | 10 |
| 5 | 9 |
| 7 | 8 |
| 9 | 7 |
| 11 | 6 |
| 13 | 5 |
| 16 | 4 |
| 18 | 3 |
| 20 | 2 |
| 22 | 1 |
| 24 | 0 |
| |------------|
| 26 | 1 |
| 28 | 2 | Clock
| 30 | 3 | faster.
|__________|____________|
* * * * *
THE OCELLATED PHEASANT.
The collections of the Museum of Natural History of Paris have just been
enriched with a magnificent, perfectly adult specimen of a species of
bird that all the scientific establishments had put down among their
desiderata, and which, for twenty years past, has excited the curiosity
of naturalists. This species, in fact, was known only by a few caudal
feathers, of which even the origin was unknown, and which figured in the
galleries of the Jardin des Plantes under the name of _Argus ocellatus_.
This name was given by J. Verreaux, who was then assistant naturalist at
the museum. It was inscribed by Prince Ch. L. Bonaparte, in his Tableaux
Paralleliques de l'Ordre des Gallinaces, as _Argus giganteus_, and a
few years later it was reproduced by Slater in his Catalogue of the
Phasianidae, and by Gray is his List of the Gallinaceae. But it was not
till 1871 and 1872 that Elliot, in the Annals and Magazine of Natural
History, and in a splendid monograph of the Phasianidae, pointed out
the peculiarities that were presented by the feathers preserved at the
Museum of Paris, and published a figure of them of the natural size.
The discovery of an individual whose state of preservation leaves
nothing to be desired now comes to demonstrate the correctness of
Verreaux's, Bonaparte's, and Elliot's suppositions. This bird, whose
tail is furnished with feathers absolutely identical with those that
the museum possessed, is not a peacock, as some have asserted, nor an
ordinary Argus of Malacca, nor an argus of the race that Elliot named
_Argus grayi_, and which inhabits Borneo, but the type of a new genus of
the family Phasianidae. This Gallinacean, in fact, which Mr. Maingonnat
has given up to the Museum of Natural History, has not, like the common
Argus of Borneo, excessively elongated secondaries; and its tail is not
formed of normal rectrices, from the middle of which spring two very
long feathers, a little curved and arranged like a roof; but it consists
of twelve wide plane feathers, regularly tapering, and ornamented with
ocellated spots, arranged along the shaft. Its head is not bare, but is
adorned behind with a tuft of thread-like feathers; and, finally, its
system of coloration and the proportions of the different parts of its
body are not the same as in the common argus of Borneo. There is reason,
then, for placing the bird, under the name of _Rheinardius ocellatus_,
in the family Phasianidae, after the genus _Argus_ which it connects,
after a manner, with the pheasants properly so-called. The specific name
_ocellatus_ has belonged to it since 1871, and must be substituted for
that of _Rheinardi_.
The bird measures more than two meters in length, three-fourths of which
belong to the tail. The head, which is relatively small, appears to be
larger than it really is, owing to the development of the piliform tuft
on the occiput, this being capable of erection so as to form a crest
0.05 to 0.06 of a meter in height. The feathers of this crest are
brown and white. The back and sides of the head are covered with downy
feathers of a silky brown and silvery gray, and the front of the neck
with piliform feathers of a ruddy brown. The upper part of the body is
of a blackish tint and the under part of a reddish brown, the whole
dotted with small white or _cafe-au-lait_ spots. Analogous spots are
found on the wings and tail, but on the secondaries these become
elongated, and tear-like in form. On the remiges the markings are quite
regularly hexagonal in shape; and on the upper coverts of the tail
and on the rectrices they are accompanied with numerous ferruginous
blotches, some of which are irregularly scattered over the whole surface
of the vane, while others, marked in the center with a blackish spot,
are disposed in series along the shaft and resemble ocelli. This
similitude of marking between the rectrices and subcaudals renders the
distinction between these two kinds of feathers less sharp than in many
other Gallinaceans, and the more so in that two median rectrices are
considerably elongated and assume exactly the aspect of tail feathers.
[Illustration: THE OCELLATED PHEASANT (_Rheinardius ocellatus_).]
The true rectrices are twelve in number. They are all absolutely plane,
all spread out horizontally, and they go on increasing in length
from the exterior to the middle. They are quite wide at the point of
insertion, increase in diameter at the middle, and afterward taper to
a sharp point. Altogether they form a tail of extraordinary length and
width which the bird holds slightly elevated, so as to cause it to
describe a graceful curve, and the point of which touches the soil. The
beak, whose upper mandible is less arched than that of the pheasants,
exactly resembles that of the arguses. It is slightly inflated at the
base, above the nostrils, and these latter are of an elongated-oval
form. In the bird that I have before me the beak, as well as the feet
and legs, is of a dark rose-color. The legs are quite long and are
destitute of spurs. They terminate in front in three quite delicate
toes, connected at the base by membranes, and behind in a thumb that is
inserted so high that it scarcely touches the ground in walking. This
magnificent bird was captured in a portion of Tonkin as yet unexplored
by Europeans, in a locality named Buih-Dinh, 400 kilometers to the south
of Hue.--_La Nature_.
* * * * *
THE MAIDENHAIR TREE.
The Maidenhair tree--Gingkgo biloba--of which we give an illustration,
is not only one of our most ornamental deciduous trees, but one of the
most interesting. Few persons would at first sight take it to be a
Conifer, more especially as it is destitute of resin; nevertheless,
to that group it belongs, being closely allied to the Yew, but
distinguishable by its long-stalked, fan-shaped leaves, with numerous
radiating veins, as in an Adiantum. These leaves, like those of the
larch but unlike most Conifers, are deciduous, turning of a pale yellow
color before they fall. The tree is found in Japan and in China, but
generally in the neighborhood of temples or other buildings, and is, we
believe, unknown in a truly wild state. As in the case of several other
trees planted in like situations, such as Cupressus funebris, Abies
fortunei, A. kaempferi, Cryptomeria japonica, Sciadopitys verticillata,
it is probable that the trees have been introduced from Thibet, or
other unexplored districts, into China and Japan. Though now a solitary
representative of its genus, the Gingkgo was well represented in the
coal period, and also existed through the secondary and tertiary epochs,
Professor Heer having identified kindred specimens belonging to sixty
species and eight genera in fossil remains generally distributed through
the northern hemisphere. Whatever inference we may draw, it is at least
certain that the tree was well represented in former times, if now it
be the last of its race. It was first known to Kaempfer in 1690, and
described by him in 1712, and was introduced into this country in the
middle of the eighteenth century. Loudon relates a curious tale as
to the manner in which a French amateur became possessed of it. The
Frenchman, it appears, came to England, and paid a visit to an English
nurseryman, who was the possessor of five plants, raised from Japanese
seeds. The hospitable Englishman entertained the Frenchman only too
well. He allowed his commercial instincts to be blunted by wine, and
sold to his guest the five plants for the sum of 25 guineas. Next
morning, when time for reflection came, the Englishman attempted to
regain one only of the plants for the same sum that the Frenchman had
given for all five, but without avail. The plants were conveyed to
France, where as each plant had cost about 40 crowns, _ecus_, the tree
got the name of _arbre a quarante ecus_. This is the story as given by
Loudon, who tells us that Andre Thouin used to relate the fact in his
lectures at the Jardin des Plantes, whether as an illustration of the
perfidy of Albion is not stated.
The tree is dioecious, bearing male catkins on one plant, female on
another. All the female trees in Europe are believed to have originated
from a tree near Geneva, of which Auguste Pyramus de Candolle secured
grafts, and distributed them throughout the Continent. Nevertheless, the
female tree is rarely met with, as compared with the male; but it is
quite possible that a tree which generally produces male flowers only
may sometimes bear female flowers only. We have no certain evidence of
this in the case of the Gingkgo, but it is a common enough occurrence in
other dioecious plants, and the occurrence of a fruiting specimen near
Philadelphia, as recently recorded by Mr. Meehan, may possibly be
attributed to this cause.
The tree of which we give a figure is growing at Broadlands, Hants, and
is about 40 feet in height, with a trunk that measures 7 feet in girth
at 3 feet from the ground, with a spread of branches measuring 45 feet.
These dimensions have been considerably exceeded in other cases. In 1837
a tree at Purser's Cross measured 60 feet and more in height. Loudon
himself had a small tree in his garden at Bayswater on which a female
branch was grafted. It is to be feared that this specimen has long since
perished.
We have already alluded to its deciduous character, in which it is
allied to the larch. It presents another point of resemblance both to
the larch and the cedar in the short spurs upon which both leaves and
male catkins are borne, but these contracted branches are mingled with
long extension shoots; there seems, however, no regular alternation
between the short and the long shoots, at any rate the _rationale_ of
their production is not understood, though in all probability a little
observation of the growing plant would soon clear the matter up.
The fruit is drupaceous, with a soft outer coat and a hard woody shell,
greatly resembling that of a Cycad, both externally and internally.
Whether the albumen contains the peculiar "corpuscles" common to Cycads
and Conifers, we do not for certain know, though from the presence of 2
to 3 embryos in one seed, as noted by Endlicher, we presume this is the
case. The interest of these corpuscles, it may be added, lies in the
proof of affinity they offer between Conifers and the higher Cryptogams,
such as ferns and lycopods--an affinity shown also in the peculiar
venation of the Gingkgo. Conifers are in some degree links between
ordinary flowering plants and the higher Cryptogams, and serve to
connect in genealogical sequence groups once considered quite distinct.
In germination the two fleshy cotyledons of the Gingkgo remain within
the shell, leaving the three-sided plumule to pass upward; the young
stem bears its leaves in threes.
We have no desire to enter further upon the botanical peculiarities of
this tree; enough if we have indicated in what its peculiar interest
consists. We have only to add that in gardens varieties exist some with
leaves more deeply cut than usual, others with leaves nearly entire, and
others with leaves of a golden-yellow color.--_Gardeners' Chronicle_.
[Illustration: THE MAIDENHAIR TREE IN THE GARDENS AT BROADLANDS.]
* * * * *
THE WOODS OF AMERICA.
A collection of woods without a parallel in the world is now being
prepared for exhibition by the Directors of the American Museum of
Natural History. Scattered about the third floor of the Arsenal, in
Central Park, lie 394 logs, some carefully wrapped in bagging,
some inclosed in rough wooden cases, and others partially sawn
longitudinally, horizontally, and diagonally. These logs represent all
but 26 of the varieties of trees indigenous to this country, and
nearly all have a greater or less economic or commercial value. The 26
varieties needed to complete the collection will arrive before winter
sets in, a number of specimens being now on their way to this city from
the groves of California. Mr. S. D. Dill and a number of assistants are
engaged in preparing the specimens for exhibition. The logs as they
reach the workroom are wrapped in bagging and inclosed in cases, this
method being used so that the bark, with its growth of lichens and
delicate exfoliations, shall not be injured while the logs are in
process of transportation from various parts of the country to this
city. The logs are each 6 feet in length, and each is the most perfect
specimen of its class that could be found by the experts employed in
making the collection. With the specimens of the trees come to the
museum also specimens of the foliage and the fruits and flowers of the
tree. These come from all parts of the Union--from Alaska on the north
to Texas on the south, from Maine on the east to California on the
west--and there is not a State or Territory in the Union which has not a
representative in this collection of logs. On arrival here the logs are
green, and the first thing in the way of treatment after their arrival
is to season them, a work requiring great care to prevent them from
"checking," as it is technically called, or "season cracking," as the
unscientific term the splitting of the wood in radiating lines during
the seasoning process. As is well known, the sap-wood of a tree seasons
much more quickly than does the heart of the wood. The prevention of
this splitting is very necessary in preparing these specimens for
exhibition, for when once the wood has split its value for dressing for
exhibition is gone. A new plan to prevent this destruction of specimens
is now being tried with some success under the direction of Prof.
Bickmore, superintendent of the museum. Into the base of the log and
alongside the heart a deep hole is bored with an auger. As the wood
seasons this hole permits of a pressure inward and so has in many
instances doubtless saved valuable specimens. One of the finest in the
collection, a specimen of the persimmon tree, some two feet in diameter,
has been ruined by the seasoning process. On one side there is a huge
crack, extending from the top to the bottom of the log, which looks as
though some amateur woodman had attempted to split it with an ax and
had made a poor job of it. The great shrinking of the sap-wood of the
persimmon tree makes the wood of but trifling value commercially.
It also has a discouraging effect upon collectors, as it is next to
impossible to cure a specimen, so that all but this one characteristic
of the wood can be shown to the public in a perfect form.
Before the logs become thoroughly seasoned, or their lines of growth at
all obliterated, a diagram of each is made, showing in accordance with
a regular scale the thickness of the bark, the sap-wood, and the heart.
There is also in this diagram a scale showing the growth of the tree
during each year of its life, these yearly growths being regularly
marked about the heart of the tree by move or less regular concentric
circles, the width of which grows smaller and smaller as the tree grows
older. In this connection attention may be called to a specimen in the
collection which is considered one of the most remarkable in the world.
It is not a native wood, but an importation, and the tree from which
this wonderful slab is cut is commonly known as the "Pride of India."
The heart of this particular tree was on the port side, and between it
and the bark there is very little sap-wood, not more than an inch.
On the starbord side, so to speak, the sap-wood has grown out in an
abnormal manner, and one of the lines indicative of a year's growth is
one and seven-eighths inches in width, the widest growth, many experts
who have seen the specimen say, that was ever recorded. The diagrams
referred to are to be kept for scientific uses, and the scheme of
exhibition includes these diagrams as a part of the whole.
After a log has become seasoned it is carefully sawed through the center
down about one-third of its length. A transverse cut is then made and
the semi-cylindrical section thus severed from the log is removed. The
upper end is then beveled. When a log is thus treated the inspector can
see the lower two-thirds presenting exactly the same appearance it did
when growing in the forest. The horizontal cut, through the sap-wood
and to the center of the heart, shows the life lines of the tree, and
carefully planed as are this portion, the perpendicular and the beveled
sections, the grain of the wood can thus be plainly seen. That these may
be made even more valuable to the architect and artisan, the right half
of this planed surface will be carefully polished, and the left half
left in the natural state. This portion of the scheme of treatment is
entirely in the interests of architects and artisans, and it is expected
by Prof. Bickmore that it will be the means of securing for some kinds
of trees, essentially of American growth, and which have been virtually
neglected, an important place in architecture and in ornamental
wood-work, and so give a commercial value to woods that are now of
comparatively little value.
Among the many curious specimens in the collection now being prepared
for exhibition, one which will excite the greatest curiosity is a
specimen of the honey locust, which was brought here from Missouri.
The bark is covered with a growth of thorns from one to four inches
in length, sharp as needles, and growing at irregular intervals. The
specimen arrived here in perfect condition, but, in order that it might
be transported without injury, it had to be suspended from the roof of
a box car, and thus make its trip from Southern Missouri to this city
without change. Another strange specimen in the novel collection is a
portion of the Yucca tree, an abnormal growth of the lily family. The
trunk, about 2 feet in diameter, is a spongy mass, not susceptible of
treatment to which the other specimens are subjected. Its bark is an
irregular stringy, knotted mass, with porcupine-quill-like leaves
springing out in place of the limbs that grow from all well-regulated
trees. One specimen of the yucca was sent to the museum two years ago,
and though the roots and top of the tree were sawn off, shoots sprang
out, and a number of the handsome flowers appeared. The tree was
supposed to be dead and thoroughly seasoned by this Fall, but now, when
the workmen are ready to prepare it for exhibition, it has shown new
life, new shoots have appeared, and two tufts of green now decorate the
otherwise dry and withered log, and the yucca promises to bloom again
before the winter is over. One of the most perfect specimens of the
Douglass spruce ever seen is in the collection, and is a decided
curiosity. It is a recent arrival from the Rocky Mountains. Its bark,
two inches or more in thickness, is perforated with holes reaching to
the-sap-wood. Many of these contain acorns, or the remains of acorns,
which have been stored there by provident woodpeckers, who dug the holes
in the bark and there stored their winter supply of food. The oldest
specimen in the collection is a section of the _Picea engelmanni_, a
species of spruce growing in the Rocky Mountains at a considerable
elevation above the sea. The specimen is 24 inches in diameter, and the
concentric circles show its age to be 410 years. The wood much resembles
the black spruce, and is the most valuable of the Rocky Mountain
growths. A specimen of the nut pine, whose nuts are used for food by the
Indians, is only 15 inches in diameter, and yet its life lines show its
age to be 369 years. The largest specimen yet received is a section of
the white ash, which is 46 inches in diameter and 182 years old. The
next largest specimen is a section of the _Platanus occidentalis_,
variously known in commerce as the sycamore, button-wood, or plane tree,
which is 42 inches in diameter and only 171 years of age. Specimens of
the redwood tree of California are now on their way to this city from
the Yosemite Valley. One specimen, though a small one, measures 5 feet
in diameter and shows the character of the wood. A specimen of
the enormous growths of this tree was not secured because of the
impossibility of transportation and the fact that there would be no room
in the museum for the storage of such a specimen, for the diameter of
the largest tree of the class is 45 feet and 8 inches, which represents
a circumference of about 110 feet. Then, too, the Californians object to
have the giant trees cut down for commercial, scientific, or any other
purposes.
To accompany these specimens of the woods of America, Mr. Morris K.
Jesup, who has paid all the expense incurred in the collection of
specimens, is having prepared as an accompanying portion of the
exhibition water color drawings representing the actual size, color,
and appearance of the fruit, foliage, and flowers of the various trees.
Their commercial products, as far as they can be obtained, will also be
exhibited, as, for instance, in the case of the long-leaved pine, the
tar, resin, and pitch, for which it is especially valued. Then, too, in
an herbarium the fruits, leaves, and flowers are preserved as nearly as
possible in their natural state. When the collection is ready for public
view next spring it will be not only the largest, but the only complete
one of its kind in the country. There is nothing like it in the world,
as far as is known; certainly not in the royal museums of England,
France, or Germany.
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