The largest telescopes in the world

The world's largest telescope today is of course the twin Keck
telescopes, even taken one by one. And before that, the largest
scope was the Russian 6-meter reflector. And before that the Hale
5-meter telescope, and before that the Hooker 2.5-meter telescope.

But before that?

I'd like to assemble a list of the world's largest telescopes, in
chronological order. Ideally it should cover all the time from
Galileo's telescope in 1609 to the present time, and be complete,
but quite naturally available information may be incomplete or
inaccurate particularly from the 1600's and 1700's.

Currently, the list looks as below. By a curious coincidence
Lord Rosse's 72-inch Leviathan was dismantled in 1908, the same
year that Mount Wilson's 60-inch reflector became operational;
since the latter happened on 20 Dec 1908, Lord Rosse's Leviathan
was most likely dismantled before that date. Thus, there ought to
be some time (several months?) during 1908 when neither the
Leviathan nor Mt Wilson's 60-inch was the world's largest telescope.
But I don't know which other telescope was the largest immediately
before Mt Wilson's 60-inch. Anybody got an idea?

I also have a lot of gaps in my list before 1783, when William
Herschel finished his 20 foot f.l. (0.43 meter aperture) reflector,
so any information there is welcome. I'm also not sure whether
Herchel's 40-foot reflector remained operational all the time
until 1845 (a few decades after Herschel's death in 1822); if not,
there's another gap there which needs to be filled.

Note that the size of scopes were usually given as the focal
length in feet; not until the Leviathan the aperture was given
as the "size" instead. Thus, both Lord Rosse's Leviathan
and Galileo Galilei's scope were 6 foot scopes.... :-)

Anyway, here's my list. Comments, additions and corrections
are welcome!

================================================== ============
World's
largest Aperture Scope
scope in

1609 0.044 m Galileos 5-6 foot f.l. refractor, x33
1640 ca ? 15-20 foot refractors
1656 0.07 m Christian Huygens 23 f.l. foot refractor, x100
1670 ca ? Hevelius 140 foot f.l. refractor
1675 (The "air telescope")

1730 ca (Large reflectors)

1774 (William Herschel starts making telescopes)
1783-1789 0.43 m William Herschel's 20 foot f.l. reflector, Bath,
England
1789-1845 1.22 m William Herschel's 40 foot f.l. reflector, Bath,
England
1845-1908 1.83 m Lord Rosse's Leviathan, 6 foot ap., Birr Castle,
Ireland; dismantled 1908
1908 ?????? ?????????? (some other scope - which?)
1908-1917 1.5 m 60-inch, Mt Wilson, California, USA; operational
20 Dec
1917-1948 2.5 m Hooker 100-inch, Mt Wilson, California, USA
1948-1974 5.0 m Hale 200-inch, Mt Palomar, California, USA
1974-1990 6.0 m Bolshoi, Nizhny Arkhyz, Russia
1990- 10.0 m Keck, Mauna Kea, Hawaii, USA
================================================== ============





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