. E. Dawes--one of Mr. Cooke's customers--purchased
an object-glass from Mr. Clark. It was so satisfactory that he ordered
several others, and finally an entire telescope. The American artist
then began to be appreciated in his own country. In 1860 he received
an order for a refractor of eighteen inches aperture, three inches
greater than the largest which had up to that time been made. This
telescope was intended for the Observatory of Mississippi; but the
Civil War prevented its being removed to the South; and the telescope
was sold to the Astronomical Society of Chicago and mounted in the
Observatory of that city.

And now comes in the rivalry of Mr. Cooke of York, or rather of his
patron, Mr. Newall of Gateshead. At the Great Exhibition of London, in
1862, two large circular blocks of glass, about two inches thick and
twenty-six inches in diameter, were shown by the manufacturers, Messrs.
Chance of Birmingham. These discs were found to be of perfect quality,
and suitable for object-glasses of the best kind. At the close of the
Exhibition, they were purchased by Mr. Newall, and transferred to the
workshops of Messrs. Cooke and Sons at York. To grind and polish and
mount these discs was found a work of great labour and difficulty. Mr.
Lockyer says, "such an achievement marks an epoch in telescopic
astronomy, and the skill of Mr. Cooke and the munificence of Mr. Newall
will long be remembered."

When finished, the object-glass had an aperture of nearly twenty-five
inches, and was of much greater power than the eighteen-inch Chicago
instrument. The length of the tube was about thirty-two feet. The
cast-iron pillar supporting the whole was nineteen feet in height from
the ground, and the weight of the whole instrument was about six tons.
In preparing this telescope, nearly everything, from its extraordinary
size, had to be specially arranged.[10] The great anxiety involved in
these arrangements, and the constant study and application told heavily
upon Mr. Cooke, and though the instrument wanted only a few touches to
make it complete, his health broke down, and he died on the 19th of
October, 1868, at the comparatively early age of sixty-two.

Mr. Cooke's death was felt, in a measure, to be a national loss. His
science and skill had restored to England the prominent position she
had held in the time of Dollond; and, had he lived, even more might
have been expected from him. We believe that the Gold Medal and