87
I.G.J, hebben gewerkt geluk te wensen met dit werk en de heer
Scheepmaker in het bijzonder voor zijn eigen, belangrijke bijdragen.
G. van Herk
The thesis of A. C. Scheepmaker (Technical University, Delft) is discussed.
His main contribution is the solution of the riddle why each evening the
first observed stars with the Danjon-astrolab usually yield negative results.
The need for comparison with recent work by Guinot is stressed as well as
more investigations with respect to heat effects.