Permissive Limits Of Ignorance And Belief In The United States

: From The Earth To The Moon

The immediate result of Barbicane's proposition was to place upon

the orders of the day all the astronomical facts relative to the

Queen of the Night. Everybody set to work to study assiduously.

One would have thought that the moon had just appeared for the

first time, and that no one had ever before caught a glimpse of

her in the heavens. The papers revived all the old anecdotes in

which the "sun of the wolves" play d a part; they recalled the

influences which the ignorance of past ages ascribed to her; in

short, all America was seized with selenomania, or had become moon-mad.



The scientific journals, for their part, dealt more especially with

the questions which touched upon the enterprise of the Gun Club.

The letter of the Observatory of Cambridge was published by them,

and commented upon with unreserved approval.



Until that time most people had been ignorant of the mode in which

the distance which separates the moon from the earth is calculated.

They took advantage of this fact to explain to them that this

distance was obtained by measuring the parallax of the moon.

The term parallax proving "caviare to the general," they further

explained that it meant the angle formed by the inclination of two

straight lines drawn from either extremity of the earth's radius

to the moon. On doubts being expressed as to the correctness of

this method, they immediately proved that not only was the mean

distance 234,347 miles, but that astronomers could not possibly

be in error in their estimate by more than seventy miles either way.



To those who were not familiar with the motions of the moon,

they demonstrated that she possesses two distinct motions, the

first being that of rotation upon her axis, the second being

that of revolution round the earth, accomplishing both together

in an equal period of time, that is to say, in twenty-seven and

one-third days.



The motion of rotation is that which produces day and night on

the surface of the moon; save that there is only one day and one

night in the lunar month, each lasting three hundred and

fifty-four and one-third hours. But, happily for her, the face

turned toward the terrestrial globe is illuminated by it with an

intensity equal to that of fourteen moons. As to the other

face, always invisible to us, it has of necessity three hundred

and fifty-four hours of absolute night, tempered only by that

"pale glimmer which falls upon it from the stars."



Some well-intentioned, but rather obstinate persons, could not

at first comprehend how, if the moon displays invariably the

same face to the earth during her revolution, she can describe

one turn round herself. To such they answered, "Go into your

dining-room, and walk round the table in such a way as to always

keep your face turned toward the center; by the time you will

have achieved one complete round you will have completed one

turn around yourself, since your eye will have traversed

successively every point of the room. Well, then, the room is

the heavens, the table is the earth, and the moon is yourself."

And they would go away delighted.



So, then the moon displays invariably the same face to the

earth; nevertheless, to be quite exact, it is necessary to add

that, in consequence of certain fluctuations of north and south,

and of west and east, termed her libration, she permits rather

more than half, that is to say, five-sevenths, to be seen.



As soon as the ignoramuses came to understand as much as the

director of the observatory himself knew, they began to worry

themselves regarding her revolution round the earth, whereupon

twenty scientific reviews immediately came to the rescue.

They pointed out to them that the firmament, with its infinitude

of stars, may be considered as one vast dial-plate, upon which the

moon travels, indicating the true time to all the inhabitants of

the earth; that it is during this movement that the Queen of

Night exhibits her different phases; that the moon is full

when she is in opposition with the sun, that is when the three

bodies are on the same straight line, the earth occupying the

center; that she is new when she is in conjunction with the

sun, that is, when she is between it and the earth; and, lastly

that she is in her first or last quarter, when she makes

with the sun and the earth an angle of which she herself occupies

the apex.



Regarding the altitude which the moon attains above the horizon,

the letter of the Cambridge Observatory had said all that was to

be said in this respect. Every one knew that this altitude

varies according to the latitude of the observer. But the only

zones of the globe in which the moon passes the zenith, that is,

the point directly over the head of the spectator, are of

necessity comprised between the twenty-eighth parallels and

the equator. Hence the importance of the advice to try the

experiment upon some point of that part of the globe, in order

that the projectile might be discharged perpendicularly, and so

the soonest escape the action of gravitation. This was an

essential condition to the success of the enterprise, and

continued actively to engage the public attention.



Regarding the path described by the moon in her revolution round

the earth, the Cambridge Observatory had demonstrated that this

path is a re-entering curve, not a perfect circle, but an

ellipse, of which the earth occupies one of the foci. It was

also well understood that it is farthest removed from the earth

during its apogee, and approaches most nearly to it at its perigee.



Such was then the extent of knowledge possessed by every

American on the subject, and of which no one could decently

profess ignorance. Still, while these principles were being

rapidly disseminated many errors and illusory fears proved less

easy to eradicate.



For instance, some worthy persons maintained that the moon was

an ancient comet which, in describing its elongated orbit round

the sun, happened to pass near the earth, and became confined

within her circle of attraction. These drawing-room astronomers

professed to explain the charred aspect of the moon-- a disaster

which they attributed to the intensity of the solar heat; only,

on being reminded that comets have an atmosphere, and that the

moon has little or none, they were fairly at a loss for a reply.



Others again, belonging to the doubting class, expressed certain

fears as to the position of the moon. They had heard it said

that, according to observations made in the time of the Caliphs,

her revolution had become accelerated in a certain degree.

Hence they concluded, logically enough, that an acceleration of

motion ought to be accompanied by a corresponding diminution in

the distance separating the two bodies; and that, supposing the

double effect to be continued to infinity, the moon would end by

one day falling into the earth. However, they became reassured

as to the fate of future generations on being apprised that,

according to the calculations of Laplace, this acceleration of

motion is confined within very restricted limits, and that a

proportional diminution of speed will be certain to succeed it.

So, then, the stability of the solar system would not be deranged

in ages to come.



There remains but the third class, the superstitious.

These worthies were not content merely to rest in ignorance;

they must know all about things which had no existence whatever,

and as to the moon, they had long known all about her. One set

regarded her disc as a polished mirror, by means of which people

could see each other from different points of the earth and

interchange their thoughts. Another set pretended that out of

one thousand new moons that had been observed, nine hundred and

fifty had been attended with remarkable disturbances, such as

cataclysms, revolutions, earthquakes, the deluge, etc. Then they

believed in some mysterious influence exercised by her over human

destinies-- that every Selenite was attached to some inhabitant

of the earth by a tie of sympathy; they maintained that the

entire vital system is subject to her control, etc. But in time

the majority renounced these vulgar errors, and espoused the true

side of the question. As for the Yankees, they had no other

ambition than to take possession of this new continent of the sky,

and to plant upon the summit of its highest elevation the star-

spangled banner of the United States of America.