The spectrograph (with a Rowland grating)
of Lowell observatory. From V. M. Slipher, "The Lowell Spectrograph",
ApJ vol. 20 (1904), 1-20.
The clock room of the 40 inch refractor
at Yerkes observatory. From George E. Hale, "The Yerkes Observatory
of the University of Chicago: IV. The Forty-Inch Telescope, Dome and Rising
Floor", ApJ vol. 6 (1897), 37-47.
A double astrograph with 15 cm aperture
and 150 cm focal length objectives, optics by Zeiss and mechanics by Heyde.
From Östen Bergstrand, Études sur la distribution de la
lumière dans la couronne solaire (L'Éclipse totale de
soleil des 20-21 août 1914, IIème partie no. 2) (Stockholm,
1919), figure 1.
Norman Lockyer's spectroscope, used
for observing the spectra of prominences outside of eclipse. From H. Schellen,
Spectrum Analysis in its Application to Terrestrial Substances, and
the Physical Constitution of the Heavenly Bodies (London, 1872), fig.
Spectrograph at the Uppsala observatory.
Illustrating the mosaic character of many astronomical instruments, the
optics for this instrument was constructed by Steinheil, while the mechanical
parts were constructed by Sörensen, instrumentmaker at the Royal Swedish
Academy of Sciences. The spectrograph was ordered by Nils Dunér,
and was finished by 1897. Photograph by Gustav Holmberg, October 1994.
© Gustav Holmberg 1994.
Zenith telescope by Warner and Swasey.
From "Telescope", Encyclopaedia Britannica, 11th edition
Solar eclipse camera used by Bernhard
Hasselberg (right) and the Royal Academy of Sciences' expedition to the
total solar eclipse of August 21 1914, stationed near Sollefteå.
The instrument had a focal length of 20 meters and used plates measuring
0.7 x 0.7 and 0.5 x 0.5 meters, exposed in the hut at left. To the right
is the lens and mirror arrangement. Picture from Hasselberg's archive at
the Uppsala University Library.
Solar eclipse camera (detail). This
is the front end of Hasselberg's camera. Note the telephone used for communicating
with personnel at the other end of the instrument. Picture from Hasselberg's
archive at the Uppsala University Library.