be doing to himself and to the cause
of astronomy by giving up his time to making telescopes for other
observers.

"Sir WILLIAM WATSON, who often in the lifetime of his father came to
make some stay with us at Datchet, saw my brother's difficulties,
and expressed great dissatisfaction. On his return to Bath he met,
among the visitors there, several belonging to the court, to whom he
gave his opinion concerning his friend and his situation very
freely. In consequence of this, my brother had soon after, through
Sir J. BANKS, the promise that L2,000 would be granted for enabling
him to make himself an instrument.

"Immediately every preparation for beginning the great work
commenced. A very ingenious smith (CAMPION), who was seeking
employment, was secured by my brother, and a temporary forge erected
in an upstairs room."

The sale of these telescopes of HERSCHEL'S must have produced a large
sum, for he had made before 1795 more than two hundred seven-feet, one
hundred and fifty ten-feet, and eighty twenty-feet mirrors. For many of
the telescopes sent abroad no stands were constructed. The mirrors and
eye-pieces alone were furnished, and a drawing of the stand sent with
them by which the mirrors could be mounted.

In 1785 the cost of a seven-foot telescope, six and four-tenths inches
aperture, stand, eye-pieces, etc., complete, was two hundred guineas, a
ten-foot was six hundred guineas, and a twenty-foot about 2,500 to 3,000
guineas. He had made four ten-foot telescopes like this for the king.
In 1787 SCHROETER got the mirrors and eye-pieces only for a
four-and-three-quarter-inch reflector for five guineas; those for his
seven-foot telescope were twenty-three guineas. Later a seven-foot
telescope, complete, was sold for one hundred guineas, and the
twenty-five-foot reflector, made for the Madrid observatory, cost them
75,000 francs = $15,000.[19] It was ordered in 1796, but not delivered
for several years, the Spanish government being short of money. For a
ten and a seven foot telescope, the Prince of Canino paid L2,310.

VON MAGELLAN writes to BODE concerning a visit to HERSCHEL:[20]

"I spent the night of the 6th of January at HERSCHEL'S, in Datchet,
near Windsor, and had the good luck to hit on a fine evening. He has
his twenty-foot Newtonian telescope in the open air and mounted in
his garden very simply and conveniently. It is moved by an