DMM 62247

Museum: Deutsches Museum, Munich

Title: Sector

Inventory number: DMM 62247

Date: To be established.

Material: Brass

Dimensions: Lenght of limb: 156 mm; width: 13,5 mm.

Description: See Schneider, 1970, p. 90.

Preliminary examination of the metallic scales: No inscription about instrument maker. Planetary symbols on the metal scale, indicated a "les Metaux". Lead symbol is absent, the scal line is present but it seems not to have a "Tin" point (the limb is cut before). Depiction of the line is very poor. Note that the origin of scales is not in the center of the little rosette, as it usually is, but just outside, about 1mm. Two other scales, each on a face, when the sector is opened at 180 degrees, on the border. "P. d. B.", side of the metallic scale. "C. d. P.", on other side. Notice that, in fact, the sector opens at a bit more than 180 degrees(!). I took measures trying to allineate the two limbs at 180 degrees. These two scales have very few values, compared to other sectors. Overall, it looks like a very cheap instrument and Schneider seems right at calling it "dilettantische". Different fonts from, say, DMM 53733. Quite small in size: a digit is about 1mm high. 

ReferencesSchneider, Ivo: Der Proportionalzirkel: Ein universelles Analogrecheninstrument der Vergangenheit. Deutsches Museum: Abhandlungen und Berichte. 38. Jahrgang 1970, Heft 2. München, Düsseldorf 1970, p. 90 f.

Measurements of Scales (in mm)

"les Metaux"

☉ [Sun, Gold]

[lead, symbol is absent] 139,5

☽ [Moon, Silver]


♀ [Venus, Copper]


♂ [Mars, Iron]


"P. d. B."

4 77,5
8 98
12 113
16 125
24 143

"C. d. P."

4 83
8 104
12 109
16 131
24 149