The Placer herald. [volume] (Auburn, Placer County, Calif.) 1855-1991, 1861-10-12

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(Sgned,) GoRrscuAKoFF
New Micrometcr for Measuring Large Dis
tances.
A a recent meeting Of the Royal As.
tronomic Society, England, Mr.. Alvan Clark,
of Boston, Mass, exhibited micrometer,
invented t.? himself which is capable of
measuring any distance up to about one de-
gree. 1t Is also furnished with position
circle. It's character is essentially the
same as that Of the parallel wire microne'
ter; but it has some peculiarlies not. it is be-
lieved, previously introduced, and on which
its wide range depends The most remarka
ble of these peculiarities consists of its be-
inc furnished with two eye pieces, composed
of small single lenses, mounted in seperate
frames, which side in a groove, and can be
separated to the required distance. A frame
carrying two parale spiderines each
mounted srperately with lis own mlcrome.
tee screw, slides IN a dove tailed groove in
front of the eye pieces: and, by a free mo,
ton in this frame, each web can be brought
opposite 10 its own eyelens. In using the
mcrometer the first step is to set the po'
sition verner to the approximate position of
the objects to be measured The frame
containing the webs and their micrometer
screws is then slilen into its place; and the
webs having been separated nearly to their
proper distances by their free motion in the
frame, they are pla"ed precisely on the Oh
iects by their fne screws, the observers eve
being carried rapidly from one eye'Iens to
the other few times, ill he is sat SIZED of
the dissection of each Of the objects by its
own web. The frame is then removed for
reading eff the measure by means of an
ochromic microscope, on the Stage of which
il is placed. One ot the webs is brought to
The intersection Of cross wires in the eye
piece of the microscope; and by turning the
screw, The revolutions OF which are conntel
the frame travels before the microscope, and
the other web is brought to the intersection
of the cross wires. The parts Of a revolu
ton are read oil by vcnire from a large
divided circle attached to the screw The
advantages arising from the peculiar con
struction of this mcrometer are the follow
inc:
|. Distances can be observed with great
accuracy up to about one degree, and the
angles OF the position also
luo WCOo oclHg III lHo I'ifthN, "lo
free from paraax. and are both equally dis
tinct, however high the magnltying power
NAV be-
3 The webs are also free from distortion
and from color.
f. A different magnifying power may be
used on each Of the objects; which may be
advantageous in comparing faint comet
with a star.
FooLsCAp PAphR.--Everybody knows
what "Foolscap paper is but would per-
haps be puzzled to tell how it come to bear
that singular cognomen. Well as fairy
tales say, once upon time, some two huu
dred years ago when Charles |. found his
revenues short, he granted certain privilel
ges amounting to monopolies. Among
these were the manufacture of paper the
exclusive right Of which was sold to, certain
parties who grew rich, and enriched the
Government at the expense Of those who
were obliged to use paper. AT this time all
the English papers bore in water marks the
Royal Arms. But the mistortunes which
attend all monarchs betel, Charles early
and when his blood had crlnsoned the scaf
fold, the Parliament under Cromwell made
Jes'S ahd JeerS aI MS Ia" III every cohceWa
manner Among other indignities to the
memory of Charles. it was ordered that the
Royal Arms be removed from the paper, and
the fools cap and bells be substituted. These
also were removed when the Rump Paria.
ment was prorogued, but paper of the sizes
of that Par!ianent's Journals still bears the
name of "Foolscap."
The Sun GOING OUT.-There are now
more spots on the sun than have been seen
for many years; some of these are visible
through smoked glass to the naked eye.
Several stars-some Of them of great brill
~ al