SCIENCES Set of 20 letters, most of them autograph and...

SCIENCES Set of 20 letters, most of them autograph and signed. Jean-Denis BARBIÉ du BOCAGE (1 autograph letter, 1 handwritten letter, and a letter concerning him), Élie de BEAUMONT (2 autograph letters), Pierre-Joseph BUC'HOZ (2 handwritten letters), Arcisse de CAUMONT (1 autograph letter), Georges CUVIER (2 items concerning him), Antoine HÉRON de VILLEFOSSE (handwritten letter), Henri MILNE EDWARDS (3 letters with autograph signatures), Auguste NÉLATON (2 letters with autograph signatures), Désiré RAOUL-ROCHETTE (letter with autograph signature), Jean ROSTAND (4 letters with autograph signatures).