D. S. (David Samuel) Margoliouth.

The Popular science monthly (Volume 19) online

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tops just catching the rays of da^vn. Down their steep sides lie the
shadows of night ; the topmost peaks alone have caught the glory !
And beyond is the night-side of the moon, illumined by dim earth-

The power is increased again, and now we are looking down into a
rrater, and behold ! one, two, three mountains rising from its central
depths ; their peaks hardly reach the level of its ring-shaped summit !

Here is another crater, with a solitary peak rising from its bottom.
See, down below, piles of rocks are lying around its base. Three miles
deep, by measurement, what awful gulfs of darkness these at the new
VOL. XIX.— 33


moon, when no light falls within their silent hollows ! What reser-
voirs of fiercest heat when, like a giant eye, the sun glares down and
floods their unsheltered spaces !

Let us turn once more to those bright fountains and rivers of
silver, astronomically called " rilles." Here they are, brilliant as ever ;
but we can learn nothing of their nature by gazing at them. The
astronomer will tell you the latest theory — namely, that when the
moon's crust was cooling, ages ago, it contracted, causing immense
corrugations, wrinkles, and nodules, and in many places deep rents,
admitting water to the heated nucleus, producing volcanic action ; in
many of these fissures rose up molten matter, filling the central open-
ings to the brim, and extending all the length of the cracks.

You have already noticed that besides the craters there are innu-
merable craterlets. Your guide will explain again — referring to some
great authority — the fanciful and plausible theory that these were the
result of downfalls of meteoric rain when the lunar crust was still in
the plastic state.

Let us observe the plains again : near the left border, under the
Bun-glare, they are too brilliant for definition of detail ; near the cen-
tral view their greenish-gray surfaces may be examined in the apparent
twilight of the moon. Their seemingly smooth character and color
prove them to be beds of oceans of the past lunar ages. These marine
bottoms are not smooth in reality, but are seamed and traversed by
ranges of hills and mountains, and craters thousands of feet deep !
Did these, like monster mouths, swallow the remnants of the evapo-
rating oceans ?

The longer one studies this lonely globe, so beautiful in its desola-
tion, the more real does it become to the eye. Here rise veritable
mountains casting their black shadows on the plains. There stretch
deserts thousands of miles in length, visible throughout all their
breadth, for there is little if any perspective on the moon.

To the east is reigning the brilliant lunar day, so long, so fierce, so
hot ; beyond it is evening, with sunset touching the mountain-peaks
on the terminator ; in the remotest west, midnight !

This is more than one can see on one's own terrestrial ball, where
the vision is bounded by atmosphere, and objects " by degrees grow
beautifully less."

One must not look at the full moon to view all these wonders, for
seen through the telescope it is merely a brilliant, dazzling sphere ;
mountains, valleys, and plains are flooded with intensest light ; no
shadows fall ; the white glitter is intolerable !

It must be viewed in six phases : the three-days-old crescent, five-
days' old, seven days' old or first quarter, the last quarter, and the last
three days of the old moon ; thus may be seen the four visible sevenths
of the lunar globe, all that is ever seen by mortal eye.

From time immemorial the graphic art has been employed in repre-


seating the moon according to the prevailing theory of the time, as
seen by the naked eye or through the telescope. In the picture-writ-
ings of both continents, in their carvings and. metal castings, were seen
the first rude presentations of the planet in her various phases.

The first astronomical moon-drawing is attributed to Anaxagoras ;
it was probably executed more than twenty-three centuries ago. Since
bis time numberless drawings have been made, all more or less imper-
fect. In 1609, Galileo, from observations made with a telescope of his
own invention, constructed the first lunar map, which is valuable only
as marking the first great advance toward precise knowledge of the
moon's surface.

Scheiner, a German professor, and Schirlaus, made numerous
sketches of a like character ; during the same century Langrenus exe-
cuted special drawings of different points on the moon, naming them
after celebrated personages.

About the year IG-tT appeared the " Selenographia," a work by
Hevelius, of Dantzic, wherein was the first lunar map at all approach-
ing correctness. Although Father Riccioli, of Bologna, published a
chart in 1651, and Dominic Cassini another in 1680, fuller as to detail,
Hevelius's chart was considered the best authority for one hundred
years after its issue, his knowledge of drawing contributing greatly to
its success.

In 1775 appeared Tobias Mayer's small lunar chart, the most accu-
rate yet published, and consulted as such until 1824. The first scien-
tific attempt to delineate the characteristic features of the moon in
detail was made by Lohrmann, a land-surveyor in Dresden : he intended
to publish a chart on a large scale in twenty-five sections, but failing
eyesight compelled him to forego his ambitious project ; he, however,
executed a fine lunar map, fifteen and a quarter inches in diameter, in

Schroeter, of Lilienthal, labored with the greatest patience, making
a long series of observations, but, owing to a lack of graphic skill,
his " Selenographische Fragmente" was not a true exponent of his

In 1837 appeared Beer and Miidler's "Der Monde," one of the
most valuable contributions to astronomical literature ; the chart ac-
companying it shows an immense amount of detail, all the principal
objects seen through the telescope being given in outline. Webb's
" Map of the Moon," reduced from this chart, is of great value to the
student, retaining as it does all the most important features and omit-
ting confusing detail.

The most interesting and wonderful chart yet published is that
recently completed by Schmidt, of Athens, the result of more than a
quarter of a century's observations of the moon, and for which the
author made more than a thousand drawings.

The most diffuse and clearly illustrated work published within the


last decade is Nelson's " Moon," the accompanying chart in sections
giving the principal features of the planet's surface. Nasmyth and
Carpenter's " Moon," illustrated by fine photographs of prominent in-
sulated peaks, mountain-ranges, and crateriform mountains, and Proc-
tor's "Motions, Aspect, Scenery, and Physical Condition of the ^loon,"
furnish delightful and instructive text to the general reader.

Very beautiful drawings of single craters, viewed under high power,
have been made by Secchi, Nasmyth, and Carpenter. Bertch, Amauld,
Temple, and Harriot, a young English astronomer, have given us topo-
graphical lunar drawings of considerable merit.

The greatest change in lunar illustration occurred in the application
of the telescope to photography. The moon, sighted by a telescope
provided with a meniscus lens for the collection of the actinic rays,
and kept in the field by the driving-clock, casts her image on a sensi-
tive plate, which, being developed, gives all the numerous details of
the lunar surface — dimly and minutely, to be sure, but capable of
enlargement and printing to apparent life-size.

Draper photographed the moon in 1840 ; Bond, in 1850 ; De La
Rue and Rutherfurd, in 1857, the former discovering that the pictures
could be combined in the stereoscope so as to appear globular. Pho-
tographic representations of the moon, in her various phases, are emi-
nently picturesque, though lacking distinct detail ; they are, however,
correct, for, granted that the apparatus is properly adjusted, the sun
paints with perfect truth.

Nelson's maps of the moon were first done in water-color. Some
have also been done in this vehicle by the "Moon Committee" of the
Royal Astronomical Society of London." It has been reserved for
Henry Harrison, a young American astronomer and artist, to paint
the first and only true telescopic portrait of the moon in oil-colors.

" Not difficult to do ! " exclaims the uninitiated observer.

"Impossible ! " returns the scientist. "No one can paint the moon
in detail."

Nevertheless, our aesthetic astronomer set to work to paint the six
phases, which would give a portrait not only picturesque, but so true
to details and coloring that it could be offered to the scrutiny of eyes
long practiced in the nightly study of the orb itself — eyes that would
be quick to detect the absence of the smallest crater, the presence of a
superfluous peak.

After the professional duties of the day, Mr. Harrison, when the
weather was propitious, passed his time in making observations of the
heavens. Seated at the telescope, he would pass hour after hour, study-
ing the surface of the lunar orb.

On one of these occasions, a summer evening, singularly calm and
clear, his wife joined him. Sitting for some time completely absorbed
in the brilliant spectacle, she at last exclaimed : " Henry, paint that, if
you can ; it is beautiful beyond description ! "



The thought had not then occurred to him. Now his wife's fan-
ciful challenge awakened a desire to paint the moon in colors ; for, as
the most exquisite portrait in black and white can not express the
bloom of lip and cheek, or the burnished gold of sunny tresses, neither
could the various astronomical drawings now in existence express the
beautiful gradations of light, the delicate tinting of the gray-green
plains, the brilliant peaks and sunlit edge that make the telescopic
moon the most interesting of celestial bodies.

Hitherto the human face and form had engaged his pencil : he
could command sittings of his subject where and when he chose ; di-
rect the light and shade ; arrange the drapery, select the pose : but
here was to be another order of affairs ; a willful, fitful queen, subject
to no human wishes, obedient to no mortal command. There were
only two evenings in the month in which to study the chosen phase —
on one of them or both her Majesty might command the vapors of the
air and veil herself in impenetrable cloud. Another month she might
summon the forces of the winds, and dance with them a demon's dance
upon the telescopic mirror ; and, on the next night, when the chosen
phase was past, appear serenely beautiful upon a field of stainless blue.

It may be fairly asked how the artist, contending with so many
difficulties, could paint a faithful portrait at all. As it would be im-
possible in the moon's short sittings, if one may use the term, to catch
and fix accurately the varied details that crowd its surface with the
pencil alone, Mr. Harrison resorted, as a first step, to photographic
aid. Taking Rutherfurd's negative of the three-days-old crescent, he
enlarged it to the desired size by means of an oxyhydrogen light,
throwing the image from the glass to his canvas. Thereon he sketched
the outlines of the craters, plains, and mountain-i-anges, as the enlarged
negative indistinctly presented them. Then, by the light of a lantern
suspended from the observatory roof, from time to time consulting the
image of the moon mirrored in the telescope, he sharpened every de-
tail, marking out the intensely black shadows and the equally intense
high lights on the topmost peaks of the terminator, the dazzling edge,
and the gradations of tint on the far-stretching plains.

Slowly — for eighteen months rolled by before the first phase was
finished — pencil and pigment, guided by artist eye and hand, did their
work, and there stood a faithful portrait of the three-days-old cres-
cent, twenty-one inches in diameter, showing the terminator at Mes-

The edge toward the left is brilliantly illuminated by the sun,
whose proximity casts a yellowish tint over the plains, that gradually
fades into grayish-green in the shadows of night on the right edge or
terminator. On the remainder of the disk, faintly illumined by earth-
light, may be dimly seen outlines of the Apennine ranges, and the
craters of Copernicus and Tycho.

The brilliant convexity of the moon is well thrown out by the clear



dark-blue of the sky in which it floats, the painted revelation of the
wonders of a sister world. Plainer than words, this colored image
tells the story of an activity of tempests, and bubbling caldrons of
fire long since burned out ; of oceans evaporated and drawn into the
deepest depths of a dying world — of present silence and empty deso-
lation !

Encouraged by the approval of famous scientists, who have exam-
ined and testified to the correctness and beauty of this first phase of
the moon, INfr. Harrison has completed a second phase, and is at work
on the remaining pictures, which are in various stages of progression.

Among the prominent features represented as seen on the tele-
scopic moon at the first quarter may be mentioned the Mare Crisium,
one of the darkest of all the regularly bordered mares or dark plains.
Crisium shows a surface of a gray tint tinged with green. At times
it is curiously dotted and streaked with light. The floor is traversed
by ridges crossing each other and throwing up small peaks. At the
first quarter appears Messier, on the terminator of the tbree-days-old
crescent. Messier is a fine crater-plain, nine miles in diameter, inclosed
by a bright mountain-wall. To the southeast rise the walls of Catha-
rina, in some places reaching a height of sixteen thousand feet above
the interior plain, which, under the highest magnifying power, shows
a surface broken up into mounds, ridges, hills, and craterlets.

Lying to the northwest appears the Mare Fcccunditatis, the largest
of the western mares or sea-beds, covering an area of one hundred and
sixty thousand square miles, and penetrating, in bay-like indentations,
into the mountain-ranges southward, Mare Tranquillitatis and Sereni-
tatis, the latter one of the most prominent gray plains seen at the first
quarter. The entire central portion of this mare shows a decided
light-green tinge.

At the last quarter the most striking feature is Copernicus, the
grandest ring-plain on the northern quadrant, and one of the most in-
structive. Its vast walls rise nearly twelve thousand feet above the
level of the plateau, showing fifty magnificent peaks that shine at cer-
tain seasons like a crown of pearls on a radiant background. The cen-
tral cones attain a height of nearly three thousand feet. On the inner
side the walls fall abruptly in terraces to the floor, while, without, they
slope gradually, and are broken into confused ridges, spreading away
from their bases into hill and movxntain chains.

Aristarchus, a bi'illiant ring-plain, is also visible at the last quarter ;
its broad, terraced walls rise twenty-six hundred feet above the moon's
surface, and seven thousand five hundred above its own interior floor,
nearly in the center of which stand two peaks and a small crater, the
central peak being the most brilliant point visible on the moon. Among
the bays, so called, seen on this quarter, is the Sinus Iridum, a dark,
semicircular level, bordered by the magnificent cliffs of one of the
most stupendous highlands of the moon, whose crest sends up at cer-


tain points towering peaks from fifteen to twenty thousand feet above
the level of the dark plain.

The Mare Imbrium, also lying in the north quadrant, is the largest
of the dark ring-plains of the moon. The lunar Carpathian and Ap-
ennine ranges bound it on the south, the Caucasus and Alps on the
west, and on the north the lofty highlands of Plato and the Sinus Iri-
dum. It has a length of seven hundred and fifty miles, and a breadth
of six hundred and seventy-eight.

One of the most wonderful and mysterious features of the mooui,
and seen on the southern quadrant, is Tycho, the center of the princi-
pal streak system. From its mountain-walled plain issue streams of
radiance like rivers of silver ; some of these " rilles " flow for a length
of a thousand miles. The southern portion of the moon is a mass of
old craters, ring-plains, valleys, hills, and ridges ; with its radiant
streak system and diversity of formations it is the most interesting
part of the lunar surface.

"When completed, this series of paintings will present not only a
worn-out world in miniature, but, if one may credit the great astron-
omers of our day, the painted prophecy of the far-off future of our
own earth, when it shall have cooled off, and all the bustling, battling
throngs of humanity be as its own clay !



IN the course of some recent inquiries into visual memory, I was
greatly struck by the frequency of the replies in which my in-
formants described themselves as subject to " visions." Those of
whom I speak were sane and healthy, but Avere subject notwithstand-
ing to visual presentations, for which they could not often account,
and which in a few cases reached the level of hallucinations. This
unexpected prevalence of a visionary tendency, among persons who
form a part of ordinary society, seems to me suggestive and worthy
of being put on record. In a previous article* I spoke of the faculty
of summoning scenes at will, with more or less distinctness, before
the visual memory ; in this I shall speak of the tendency among
sane and healthy persons to see images flash unaccountably into

Many of my facts are derived from personal friends of whose ac-
curacy I have no doubt. Another group comes from correspondents
who have written at length with much painstaking, and whose letters

* See a previous article on " Mental Imagery," " Popular Science Monthly," vol. xviii,
p. 64.


appear to me to bear internal marks of scrupulous truthfulness. A
third part has been collected for me by many kind friends in many
countries, each of whom has made himself or herself an independent
center of inquiry ; and the last, and much the most numerous portion,
consists of brief replies by strangers to a series of questions contained
in a circular that I drew up. I have gone over all this matter with
great care, and have cross-tested it in many ways while it was accu-
mulating, just as any conscientious statistician would, before I began
to form conclusions. I was soon convinced of its substantial trust-
worthiness, and that conviction has in no way been shaken by subse-
quent experience. In short, the evidence of the four groups I have
just mentioned is quite as consistent as could have been reasonably

The lowest order of phenomena that admit of being classed as
visions are the " Number forms " to which I have drawn attention on
more than one occasion, but to which I must again very briefly allude.
They are an abiding mental peculiarity in a certain proportion of
persons (say five per cent.), who are unable as adults, and who have
been ever unable as far back as they can recollect, to think of any
number without referring it to its own particular habitat in their men-
tal field of view. It there lies latent, but is instantly evoked by the
thought or mention of it, or by any mental operation in which it is
concerned. The thought of a series of consecutive numbers is there-
fore attended by a vision of them arranged in a perfectly defined and
constant position, and this I have called a " Number form." Its origin
can rarely be referred to any nursery diagram, to the clock-face, or to
any incident of childhood. Nay, the form is frequently unlike any-
thing the child could possibly have seen, reaching in long vistas and
perspectives, and in curves of double curvature. I have even had to
get wire models made by some of my informants in explanation of
what they wished to convey. The only feature that all the forms
have in common is their dependence in some way or other upon the
method of verbal counting, as shown by their angles and other di-
visions occurring at such points as those where the 'teens begin, at the
twenty's, thirty's and so on. The forms are in each case absolutely
unchangeable, except through a gradual development in complexity.
Their diversity is endless, and the Number forms of different men are
mutually unintelligible.

These strange " visions," which are extremely vivid in some cases,
are almost incredible to the vast majority of mankind, who would set
them down as fastastic nonsense, but they are familiar parts of the
mental furniture of the rest, where they have grown naturally, and
where they remain unmodified and unmodifiable by teaching. I have
received many touching accounts of their childish experiences from
persons who see the Number forms, and the other curious visions of
which I shall speak. As is the case with the color-blind, so with these


seers. They imagined at first that everybody else had the same way
of regarding things as themselves. Then they betrayed their pecul-
iarities by some chance remark which called forth a stare of surprise,
followed by ridicule and a sharp scolding for their silliness, so that the
poor little things shrunk back into themselves, and never ventured
again to allude to their inner world. I will quote just one of many
similar letters as a sample. I received this, together with much in-
teresting information, immediately after a lecture I gave last autumn
to the British Association at Swansea,* in which 1 had occasion to
speak of the Number forms. The writer says :

I had no idea, for many years, that every one did not imagine numbers in the
same positions as tliose in which they appear to me. One unfortunate day I
spoke of it, and was sharply i-ebuked for my absurdity. Being a very sensitive
cliild, I felt this acutely, but nothing ever shook my belief that, absurd or not, I
always saw numbers in this particular way. I began to be ashamed of what I
considered a peculiarity, and to imagine myself, from this and various other
mental beliefs and states, as somewhat isolated and pecuUar. At your lecture
the other night, though I am now over twenty-nine, the memory of my childish
misery at the dread of being peculiar came over me so strongly that I felt I
must thank you for proving that, hi this particular, at any rate, my case is most

The next form of vision of which I will speak is the instant asso-
ciation of color with sound, which characterizes a small percentage of
adults, but apears to be rather common, though in an ill-developed
degree, among children. I can here appeal not only to my own col-
lection of facts, but to those of others, for the subject has latterly
excited some interest in Germany. The first widely known case was
that of the brothers Nussbaumer, published in 1873 by Professor
Bruhl, of Vienna, of which the English reader will find an account in
the last volume of Lewis's " Problems of Life and Mind," page 280.
Since then many occasional notices of similar associations have ap-
peared, but I was not aware that it had been inquired into on a large
scale by any one but myself. However, I was gratified by meeting
with a pamphlet a few weeks ago, just published in Leipsic by two
Swiss investigators, Messrs. Bleuler and Lehmann. Their collection
of cases is fully as large as my own, and their results in the more im-
portant matters are similar to mine. One of the two authors had the
faculty very strongly, and the other had not ; so they worked con-
jointly with advantage. As my present object is to subordinate de-
tails to the general impression that I wish to convey of the visionary
tendency of certain minds, I will simply remark, first, that the per-
sistence of the color association with sounds is fully as remarkable as
that of the Number form with numbers. Secondly, that the vowel-
sounds chiefly evoke them. Thirdly, that the seers are invariably
most minute in their description of the precise tint and hue of the

* See *' Fortnightly Review," September, 1880.


color. They are never satisfied, for instance, with saying " blue," but
will take a great deal of trouble to express or to match the particular
blue they mean. Lastly, no two people agree, or hardly ever do so, as

Online LibraryD. S. (David Samuel) MargoliouthThe Popular science monthly (Volume 19) → online text (page 64 of 110)