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Was every individual recommendation it
contained, not merely unfit to be adopted, but so totally
deficient in plausibility as to be utterly unworthy of
discussion? Or did the President and his officers feel, that
their power rested on an insecure foundation, and that they did
not possess the confidence of the working members of the
Society?
CHAPTER V
OF OBSERVATIONS
There are several reflections connected with the art of making
observations and experiments, which may be conveniently arranged
in this chapter
OF MINUTE PRECISION
No person will deny that the highest degree of attainable
accuracy is an object to be desired, and it is generally found
that the last advances towards precision require a greater
devotion of time, labour, and expense, than those which precede
them The first steps in the path of discovery, and the first
approximate measures, are those which add most to the existing
knowledge of mankind
The extreme accuracy required in some of our modern inquiries
has, in some respects, had an unfortunate influence, by favouring
the opinion, that no experiments are valuable, unless the
measures are most minute, and the accordance amongst them most
perfect It may, perhaps, be of some use to show, that even with
large instruments, and most practised observers, this is but
rarely the case The following extract is taken from a
representation made by the present Astronomer-Royal, to the
Council of the Royal Society, on the advantages to be derived
from the employment of two mural circles:--
"That by observing, with two instruments, the same objects at the
same time, and in the same manner, we should be able to estimate
how much of that OCCASIONAL DISCORDANCE FROM THE MEAN, which
attends EVEN THE MOST CAREFUL OBSERVATIONS, ought to be
attributed to irregularity of refraction, and how much to THE
IMPERFECTIONS OF INSTRUMENTS
In confirmation of this may be adduced the opinion of the late M
Delambre, which is the more important, from the statement it
contains relative to the necessity of publishing all the
observations which have been made
"Mais quelque soit le parti que l'on prefere, il me semble qu'on
doit tout publier Ces irregularites memes sont des faits qu'il
importe de connoitre LES SOINS LES PLUS ATTENTIFS N'EN
SAUROIENT PRESERVER LES OBSERVATEURS LES PLUS EXERCES, et celui
qui ne produiroit que des angles toujours parfaitment d'accord
auroit ete singulierement bien servi par les circonstances ou ne
seroit pas bien sincere--BASE DU SYSTEME METRIQUE, Discours
Preliminaire, p
This desire for extreme accuracy has called away the attention of
experimenters from points of far greater importance, and it seems
to have been too much overlooked in the present day, that genius
marks its tract, not by the observation of quantities
inappreciable to any but the acutest senses, but by placing
Nature in such circumstances, that she is forced to record her
minutest variations on so magnified a scale, that an observer,
possessing ordinary faculties, shall find them legibly written
He who can see portions of matter beyond the ken of the rest of
his species, confers an obligation on them, by recording what he
sees; but their knowledge depends both on his testimony and on
his judgment He who contrives a method of rendering such atoms
visible to ordinary observers, communicates to mankind an
instrument of discovery, and stamps his own observations with a
character, alike independent of testimony or of judgment
ON THE ART OF OBSERVING
The remarks in this section are not proposed for the assistance
of those who are already observers, but are intended to show to
persons not familiar with the subject, that in observations
demanding no unrivalled accuracy, the principles of common sense
may be safely trusted, and that any gentleman of liberal
education may, by perseverance and attention, ascertain the
limits within which he may trust both his instrument and himself
If the instrument is a divided one, the first thing is to learn
to read the verniers If the divisions are so fine that the
coincidence is frequently doubtful, the best plan will be for the
learner to get some acquaintance who is skilled in the use of
instruments, and having set the instrument at hazard, to write
down the readings of the verniers, and then request his friend to
do the same; whenever there is any difference, he should
carefully examine the doubtful one, and ask his friend to point
out the minute peculiarities on which he founds his decision
This should be repeated frequently; and after some practice, he
should note how many times in a hundred his reading differs from
his friend's, and also how many divisions they usually differ
The next point is, to ascertain the precision with which the
learner can bisect an object with the wires of the telescope
This can be done without assistance It is not necessary even to
adjust the instrument, but merely to point it to a distant
object When it bisects any remarkable point, read off the
verniers, and write down the result; then displace the telescope
a little, and adjust it again A series of such observations
will show the confidence which is due to the observer's eye in
bisecting an object, and also in reading the verniers; and as the
first direction gave him some measure of the latter, he may, in a
great measure, appreciate his skill in the former He should
also, when he finds a deviation in the reading, return to the
telescope, and satisfy himself if he has made the bisection as
complete as he can In general, the student should practise each
adjustment separately, and write down the results wherever he can
measure its deviations
Having thus practised the adjustments, the next step is to make
an observation; but in order to try both himself and the
instrument, let him take the altitude of some fixed object, a
terrestrial one, and having registered the result, let him
derange the adjustment, and repeat the process fifty or a hundred
times This will not merely afford him excellent practice, but
enable him to judge of his own skill
The first step in the use of every instrument, is to find the
limits within which its employer can measure the SAME OBJECT
UNDER THE SAME CIRCUMSTANCES It is only from a knowledge of
this, that he can have confidence in his measures of the SAME
OBJECT UNDER DIFFERENT CIRCUMSTANCES, and after that, of
DIFFERENT OBJECTS UNDER DIFFERENT CIRCUMSTANCES
These principles are applicable to almost all instruments If a
person is desirous of ascertaining heights by a mountain
barometer, let him begin by adjusting the instrument in his own
study; and having made the upper contact, let him write down the
reading of the vernier, and then let him derange the UPPER
adjustment ONLY, re-adjust, and repeat the reading When he is
satisfied about the limits within which he can make that
adjustment, let him do the same repeatedly with the lower; but
let him not, until he knows his own errors in reading and
adjusting, pronounce upon those of the instrument In the case
of a barometer, he must also be assured, that the temperature of
the mercury does not change during the interval
A friend once brought to me a beautifully constructed piece of
mechanism, for marking minute portions of time; the three-
hundredth parts of a second were indicated by it It was a kind
of watch, with a pin for stopping one of the shop hands
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Solution to the Taishi House, so that Qin Hui to me as a gift, the return of the Lord King. I am in jail know the truth cartier replica watch of the Southern Song Dynasty, after jumping a small move, where can endure that evening to kill prison guards, escape flee. !and!quotLiu Yuanjia heaved a long breath, said!and!quot Since then, I am disheartened affairs of state, simply on the rivers and lakes begin to steal. I escaped from the palace of the Jin, he had stolen the Golden Palace dig some of the precious pearl, more than ten years, or that criminal syndicates have also received a lot of money to make a living, so three years ago, quit that the expansion of this garden. Although I did not say rich worthy enemy, but also comparable to the nobility of Chake. Haha, I can not think of the rich and powerful, the former years to arrest me Guanfu myself, I have now is cartier man watch the fear of collusion, collusion unlikely. Of course, much less who would dare to ask me the origins of the!, ha ha, ha ha! !and!quot
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They are subjected to siege, or I give them salvation. Does she know coral is my maid? Is really chanel earrings ridiculous, outrageous! !and!quotStruck by this idea does not have to find that coral turned itself inside out, Xingmou semi-Kai, groaning, said!and!quot Water, water, I would like chanel necklace to chanel pearls drink. !and!quotGENG was about to give her brought, Penglaimonv said!and!quot Wait a minute! !and!quotStopped coral right hand, took out a Silver Needle Tiaopo her middle finger and saw a black Xue Jian Yi Gu ejected, fishiness servant nose, after a long while, blood gradually bright red, coral eyes open come.
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???? He will drag antelope nearly 200 meters away from the oasis outside the drop, and then release the bandage, and use sword in the antelope!and!39s body on the gash several large wounds, a lot of blood suddenly flooded out of the air Misan Zhao Hui San not to the smell of blood. Everything is ready, Lei shaking quickly dolce
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