The Flagstaff sun-democrat. [volume] (Flagstaff, Ariz.) 1896-1897, 1897-05-27
Two Great Lenses.

CAMBRIDGE. Mass, May Zz-frnm
Clark's Lense Works. Cambridge. has
been shipped in special parlor car
two disks which form the lenses for the
Yerkes telescope, the largest lenses ever
made. The car was attached to the
Chicago express. Professor Clark. the
maker Of the lenses; Carl Lubn. his
foreman, who has spent several years
10 polishing the great disks. aud
another workman accompanied the
valuable cargo.
The greatest care was taken that M
harm should befall The two disks and
10 their large cases in the center Of the
ear they were SO adjusted on springs
that the jolting will not damage them
Tho guards have b,.-u stationed at both
doors OF the car ard every precaution
taken that outsiders aud curiosity
seekers shall in no way interfere with
the transfer Of the lenses. Then. too
they were Insured for their full value
while In transit.
This Ysrkes lense il the largest aud
6nest IN the word IL represents
nearly six years II careful labor aud
completed is valued ~ 500. 900. The
glass came from the factory II MAN.
tots, 10 Paris, Franc. ina lense is A
inches gu the surface IN diameter ami
weighs SIS pounds. rns exposed sur.
face or aperture is f,riy inches, ,hr
other inch aud haif h-iag taken up
by the casing. This make, il just four
inches larger that tn Lick telescop.
lense, which was AIS. utie by the
Clarks and has held the place Of honor
In the world of astronomy.
The great lense consist. If two ST.
parate lenses IT differing density aud
shape, separated whes IN use by a
space Of several inches Tue outer one,
which comes in contact with the AT mos.
phere, 10 made Of n perfect piece Il
crown glass. It is double convex. two
and three-quarters If an inch at the
edge, aud weighs 205 pounds. The inner
lens is made Of flint glass, aud is what
is known AS plano concsve. II is one
and one-eighth inches IN thickness at
the center aud two incnis AZ the edge;
it weighs $40 pounds.
Both Tense are a,iJ,-,et ~ an iron
ring and cell and the D,.a. w,rgnt of the
glass aud iron casiDs /, /. 800 pounds.
Toe focal distance of ~, itiss Is sixty
one feet. The packing II the leases
WAS Que of Tho most interesting
features in their history. FIRST they
were carefully aud smoothly wrapped
IN hanne, sewed tightly AT the edges;
then they were covered with several
,hicknesses If soft tissue paper, aud
then wrapped in hard paper aud en-
cssed in bed Of cotton batting, silk
and curl-d hair in n strong box.
This box was mounted upon springs
and placed in a larger box and packed
with excelsior. The springs within
the outer casing. between that aud the
inner box. are drsigued To detract from
any jar That the outer CASE may sustain
and thus save the lense from the affects
Of almost any shock.
The great glass disks for these lenses
were Cut il Paris and year was taken
up in preparing The material aud cast
ing y ,s,u % mIre before y perfect
QUE was secured.
The care, the skill. the pstience
which have been expended in grinding
the lsus.s is marvellous. When COM
pietsd Inc lenss WAS mounted In tent
porary telescope tube and tested for
tifly nights aud found perfect. Had
there been y deviation of y spiders
slrud IL would have besn useless.