Date: 01/01/1850
From: A. Quetelet
To:
Date: 05/01/1850
From: Charles Rogier, ministre de l'Intérieur
To: A. Quetelet
Date: 08/01/1850
From: Arsène Beaulieu, mécanicien
To: A. Quetelet
Date: 09/01/1850
From: Arsène Beaulieu, mécanicien
To: A. Quetelet
Date: 12/01/1850
From: Arsène Beaulieu, mécanicien
To: A. Quetelet
Date: 14/01/1850
From: A. Quetelet
To: Charles Rogier, ministre de l'Intérieur
Date: 15/01/1850
From: Charles Rogier, ministre de l'Intérieur
To: A. Quetelet
Date: 16/01/1850
From: Charles Rogier, ministre de l'Intérieur
To: A. Quetelet
Date: 18/01/1850
From: Eugène Vanderbelen, chef de division au Ministère de l'Intérieur
To: A. Quetelet
Date: 31/01/1850
From: A. Quetelet
To: Louis Désiré Grégoire, aide à l’Observatoire