1074 SEC. 20. MISCELLANEOUS. 



plate bearing the prism. (C.) Cathetometor, with movable ocular thread, 

 allowing a reading of yi- millimetres. 



5. Magnetic instruments, according to Larnont, made by Dr. Carl, of 

 Munich, Bavaria : (A.) Theodolite, for the absolute measurement of declina- 

 tion and of the horizontal component. The two microscopes alloAv the reading 

 of the second. (B.) Instruments to measure the variations of the horizontal 

 component and of the inclination. 



6. Differential interrupter, made by Prof. Blaserna, for the study of 

 currents induced and of the extra currents. Full description given iii the 

 " Giornale d^ Scienze Natural! ed Economiche," Palermo, 1 870. Sensitive 

 from TooNroo to T^THK".- 



7. Electric and magnetic apparatus, for measurement and by projection: 

 (A.) Quadrant galvanometer, by Dr. Carl, for instruction purposes, with two 

 threads, one thick and snort, the other fine and long. (B.) Sine and tangent 

 compasses. (C.) Apparatus of projection, by Prof. Blaserna, for the demon- 

 stration of magnetic phenomena, provided with two arresters of the oscilla- 

 tions, one by water and the other of thick brass, for experiments in deviation 

 and oscillation. (D.) Electrometer (Thomson), according to Kirchhoff, for 

 projection. (E.) Wiedemann's compass, with three pairs of spirals by Kipp. 



8. Electric apparatus, for measurement and by projection : (A.) Bifilar 

 electrometer of Palmier!, made by De Palma. of Naples. (B.) Edelmann's 

 compass. (C.) Thomson's galvanometer. (D.) Wheatstoue's rheostat. 



9. Electric apparatus, for measurement and by projection : Wheatstone's 

 bridge, made by Stb'hrer, of Leipsic, with its commutator, Kipp's rheostat. (B.) 

 Astatic galvanometer, with a very short thread, to show the thermo-electric 

 currents, and currents of terrestrial induction by projection, made by 

 Campbell. (C.) Astatic galvanometer, with a long thread and reflector, made 

 by Ruhrnkorff. (D.) Electric multiplier, by Belli. 



10. (A.) Perfected Kipp's chronoscope, with apparatus for the fall of 

 weights. (B.) Kipp's chronograph. 



4562. Fhotographa-representing various Scientific In- 

 struments in the Cabinet of Geodesy and Hydrometry, Royal 

 University of Padua. P ro f- Legnazzi, Director, Padua. 



GROUP I. TELESCOPES, SQUARES, AND PRISMS. 



1. Ramsden's Dynamometer, made in the workshops of the Royal Observa- 



tory of Padua (1866). 



2. Dioptric with pointers by the Giuseppe Stefan!, of Padua (1827). 



3. Squares with triangular prism, by Ertel, of Monaco (1872). 



4. Square of Wollaston, by Merlo, of Milan (1869). 



5. Model of telescope for public instruction, designed by Professor Leg- 



iiazzi, and constructed by Francesco Pasini (1875). 



6. Achromatic telescope by the celebrated Geo. Dollond, of London 



(1740). 



7. Telescope with distance-measurer, by Rochon (1828). 



8. Land surveying squares, simple, from the workshop of the Royal Obser- 



vatory of Padua. 



9. Heliotrope, by Ertel, of Monaco (1873). 



10. Camera Lucida, by the distinguished optician Ainici, of Florence (1836). 



11. Reflection square from the Teciiomanasio of Milan (1868). 



12. Reflection square and allineator, by Goldschmid, of Zurich (1872). 



13. Seconds counter, by Ertel, of Monaco (1874). 



14. Telescope with distance-measurer, by Rochon (1869). 



15. Terrestrial telescope, by the optician Plossl, of Vienna (1845). 



16. Pantometer, with compass from the Tecnomanasio of Milan (1864). 



