Signature |
Maker |
Instruments |
Comments |
Location |
References |
ERTEL UND SOHN |
Germany, fl.1834-58, MIM OIM |
Transit Instrument and Mural Circle of the U.S. Naval Observatory, 1845; Naval Theodolite = ADL-L28; Plotting Scale = ADL-M133; Sextant = DEU; Computing Rule, 1843 = P.C.; Altazimuth Instrument = WHI; Level = WHI; Theodolites = KEN, P.C.(1987). |
T.L. and Georg Ertel; sometimes spelled "Ertell"; trade catalogue, 1847. |
Munich. |
Engelmann 1; USNM; Italian Inv.; Chaldecott 3; RGO; RSW; J.A. Bennett 2; ADL. |
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