‎"ROEMER (RÖMER), OLE - THE PLAN FOR ""OBSERVATORIUM TUSCULANUM""‎
‎Olai Roemeri ad G.G. Leibnitium Epistola de Instrumento Astronomicis Observationibus serviente à se inventa. (Dated Hafniæ 15. Dec. 1700). ‎

‎Berlin, Ambrosius Haude, 1727. 4to. Contemp. full calf. Raised bands. Tome- and titlelabels with gilt lettering. Minor repairs at upper joint. In: ""Miscellanea Berolinensia, ad Incrementium scientiarum ex Scriptis Societati Regiæ Scientiarum exhibitis editia, Continuatio II."" (6),346,(4) pp., 11, partly folded engraved plates. Scattered brownspots. Roemer's letter to Leibniz: pp. 276-78, 2 textillustrations. The entire volume offered.‎

Reference : 59045

‎First printing of Roemer's letter to Leibniz in which he describes his plan for a new observatory and the circle-instrument.""In a letter written to Leibniz, dated December 15, 1700, - (the offered item) - in reply to Leibniz's request for the most suitable plan for an observatory, Roemer describes his plans for the ""Observatorium Tusculanum"". He has an excellent discussion of the need of building the observatory so that it can best serve the function for which it is intended, namely, observation. He probably was thinking of the construction of the Paris Observatory, a beautiful building, but impractical as far as actual observational needs were concerned. He also describes the prime vertical transit and states his preference for the circle as compared to quadrants and sextants, saying that he would have confidence in a circle of four feet in diameter than a quadrant of ten."" (I. Bernard Cohen in ""Roemer and the first determination of the Velocity of Light"", p. 48).‎