Correspondents
Full information on contents and repositories of this correspondence can be
found in:
Petra van der Heijden: The "Lost Letters" of J.C. Kapteyn, in The Legacy of J.C. Kapteyn. Studies on Kapteyn and the Development of Modern Astronomy, eds. P.C. van der Kruit and K. van Berkel. Astrophysics and Space Science Library, Volume 246, Kluwer Academic Publishers, Dordrecht
For biographical information on the correspondents, see this excellent page:
History of Astronomy: Persons (Wolfgang R. Dick, Bonn)
The letters residing at the University of Helsinki Observatory (linked) have been carefully scanned and made available by Paavo Piironen and Eva Isaksson in June 2002. Thank you!!
INDIVIDUAL CORRESPONDENTS
W.S. Adams (1876-1956) - ~ 30 letters
E.E. Barnard (1857-1923) - > 6 letters
Bourget? - 2 letters
W.W. Campbell (1862-1938) - ~ 10 letters
C.V.L. Charlier (1862-1934) - 2 letters
W.H.M. Christie (1845-1922) - a few letters
F. Cohn (1866-1921) - 4 letters
Darmstädter - 1 letter
A.S. Donner (1854-1938) - ~ 80 letters
F.W. Dyson (1868-1939) - ~ 15 letters
P. Ehrenfest (1880-1933) - 15 letters
G. Forbes (1849-1936) - > 2 letters
E.B. Frost (1866-1935) - 110 letters
R. Furuhjelm (1879-1944) - 11 letters
D. Gill (1843-1914) - ~ 130 letters
G.E. Hale (1868-1938) - ~ 850 pages!
E. Hertzsprung (1873-1967) - > 128 letters
E.S. Holden (1846-1914) - > 2 letters
C.E. Kalshoven (1855-19??)
P. Lowell (1855-1916) - 1 letter
H.A. Lorentz (1853-1928) - 5 letters
F. Neesen - 1 letter
S. Newcomb (1835-1909) - ~ 50 letters
J.H. Oort (1900-1992) - 6 letters
J.A. Parkhurst - ~ 12 letters
E.C. Pickering (1846-1919) - ~ 100 letters
A.W. Roberts (1857-1937) - 2 letters
H.N. Russell (1877-1957) - 6 letters
E.F. van de Sande Bakhuyzen (1848-1918) - 20 letters
F. Schlesinger (1871-1943) - > 17 letters
K. Schwarzschild (sr.) (1873-1916) - > 26 letters
F.H. Seares (1873-1964) - ~ 140 letters
H. Shapley (1885-1972) - 18 letters
W. de Sitter (1872-1934) - ~ 20 letters
V.M. Slipher (1875-1969) - 1 letter
S.E. Strömgren (sr.) (1870-1947) - 25 letters
M. Wolf (1863-1932) - 14 letters
Ch.A. Young (1834-1908) - 3 letters
F. Zernike (1888-1966) - 6 letters
CORRESPONDING INSTITUTIONS
National Academy of Sciences, Washington DC, USA - 1 letter
Royal Society, London - 2 letters
Royal Astronomical Society, London - a few letters
Royal Swedish Academy of Sciences, Stockholm - 1 letter
Smithsonian Institution, Washington DC, USA - 3 letters
