Archives

Fraunhofer’s explanation of haloes around the sun and moon as diffraction phenomena

  FRAUNHOFER, Joseph. Theorie der Höfe, Nebensonnen und verwandter Phänomene mit Versuchen zur Bestätigung derselben. Offprint from Astronomische Abhandlungen (H. C. Schumacher, ed.), Drittes Heft. N.p., n.d. [Altona: Hammerich- und Heineking’schen Buchdruckerey, 1825?]   First edition, extremely rare separately-paginated offprint (journal pagination 31-92) of this work on atmospheric optical phenomena, including haloes and parhelia. “Fraunhofer (1787-1826) was the first to interpret haloes around the sun and moon as diffraction phenomena. The fog particles that produce the aureole are transparent and Fraunhofer experimented Read More...

Brendel Drosera Botanical Model, c. 1880

A Brendel Drosera rotundifolia or sundew botanical model of the 1880’s. The model is a 20 times enlarged depiction. Brendel made the model with its bristles of glass enclosing an insect. On original turned wooden ebonized stand with original blue label with nr. 130, corresponding with the catalogue. The model has some damages due to it’s age and fragility. Length: 38 cm. Read More...

Large correction collar objective – Carl Zeiss.

The canister lid is engraved, ‘C. Zeiss, Jena. 1/12’. 1/12″ correction collar Read More...

Miniature globe by Carl Bauer made circa 1820/1830

Miniature globe signed “CB” for Carl Bauer in wooden case. Condition: very good. Dimensions (case): height 7 cm x diameter 5.6 cm Nuremberg made circa 1820/1830.   Read More...

Compass made in Germany circa 1730 in its original case

Unsigned compass, Germany circa 1730. Circular compass in gilded and silvered brass resting on a square gilded brass plate entirely engraved with acanthus leaves and scrolls.  The blued steel needle has a brass pivot that can be locked by a small system.  The bottom of the compass is engraved with the 4 cardinal points and an arrow indicating the magnetic declination at approximately 12° West. The whole thing is covered in glass.  The back of the instrument is unengraved, revealing two screws that Read More...

Brass sector signed Peter Rahne Fecit Zu Berlin made circa 1740

Brass sector signed “Peter Rahne Fecit Zu Berlin” composed of two flat rulers with curved ends.   A rosette is engraved on both sides of the hinge.   The instrument features 8 scales of proportion, 3 on one side and 5 on the other.   On the signature side are the following 3 scales: Lin Metall, Chord, Cubica, and on the other side: Fortifica, Arithm, Geome, lb Plum, lb Ferr.   An inch scale has been regrafted inside the branches.   Note the presence of Read More...

Rare dividers signed Michael Schultz and dated 1624

Elegant brass and steel dividers with decorated handles and hinge.   One of the points is removable.   The compass head features two raised rosette-shaped nuts similar to those found on models by Christoph Dreßler (similar models in the Kern collection).   Dimension: 15,3 cm long   Signed MS (for Michael Schultz) and dated 1624 inside. Read More...

First complete edition of Schwenter’s treatise on geometry and its applications to surveying

SCHWENTER, Daniel. Geometriae practicae novae. Tractatus I. Darinnen auss rechtem Fundament gewisen wird. Wie man in der Geometria auff dem Papier und Lande, mit denen darzu gehörigen Instrumenten, als Cirkel, Richtscheid, Winkelhacken [et]c. Ja zür noht ohne die selben verfahren unnd operirn solle . . . Tractatus II. Ohne einig künstlich Geometrisch Instrument allein mit der Messrute und etlichen Stüben das Land zu messen. Tractatus III. Mensula Prætoriana. Beschreibung dess Nutzlichen Geometrisch Tischleins, von dem fürtresslichen und weitberühmten Mathematico Read More...

A gilded German compendium by the maker of the first map of Munich – Volckmer

VOLCKMER (Tobias), Astronomical compendium in gilt and silver brass and silver signed « Tobias Volckmer fecit anno 1641 ».  Gilded brass and silver. The instrument measures 95x95x30mm closed.     A beautiful instrument typical of the Volckmers’ production. The compendium is composed of a geometric astronomical quadrant with movable alidade decorated with fruits and mascarons, a horizontal sundial set for 48° North latitude – i.e. that of Munich where Volckmer was based -, a large rotating compass with a wind rose, two sides without Read More...

Bramer’s description of his improved version of Galileo’s proportional compass, 1615

BRAMER, Benjamin. Beschreibunge und Underricht wie allerley Theylungen zu den Mathematischen Instrumenten zu verfertigen: neben dem Gebrauch eines newen Proportional Instruments in zweyen Theylen verfasset. Marburg: Paul Egenolff, 1615. First edition, extremely rare, of Bramer’s work describing a new kind of sector, or proportional compass, having more sophisticated scales than Galileo’s model – the sector was the earliest multi-purpose mechanical calculating device. This work is one of only a handful of very rare tracts on the sector published in the Read More...

Eulenberg Baresthesiometer, C1910

Albert Eulenburg (1840-1917)  studied medicine at the Universities of Berlin, Bern and Zurich. He became a professor of pharmacology at the University of Greiswald, and in 1882 a professor of neurology in Berlin. He is best known for his magisterial multi-volume Real-Encyclopädie der gesammten Heilkundes–published in four editions between 1880 and 1914. He introduced his  barersthesiometer  in the 1890s and it soon became widely adopted for the measurement of sensitivity to pressure, an important diagnostic marker in various neurological Read More...

Tulip frame German sextant in case – ‘Eigens Fabrikat’.

A Victorian brass tulip frame sextant, German manufactur. The silver scale is engraved from -10 to 130. There are 7 sun filters, all damage free and two mirrors. Both mirrors have slight deterioration but generally good.  The end of the arm is signed, ‘Eigens Fabrikat’ (Own Factory). With mahogany handle to the rear (damage free). In mahogany case with two telescopes and sun filter.   Read More...