892 SEC. 20. COLLECTION OF APPARATUS AND PHOTOGRAPHS 



19. Level, system Egault, with telescope (1861). 



20. Bubble, fitted by Rocchetti, of Padua (1844). 



21. Barometer, Gay Lussac (1830). 



22. Barometer, Fortin, by Rocchetti, of Padua (1850). 



23. Water level with telescope ; an historical piece ; must be at least two 



centuries and a half old. 



24. Ecclimeter, by Rocchetti, which also serves as a level (1847). 



25. German Biffa, system Stampfer (1856). 



26. Italian Biffa, by Rocchetti, of Padua (1849). 



27. Speaking Biffa (1862). 



28. Egyptian Biffa (1862). 



29. Old Italian Biffa (1812). 



30. German Biffa, system Stampfer (1856). 



31. Biffa, Milesi (1874). 



GROUP V. PLANIMETERS, COMPASSES, AND INSTRUMENTS OF 

 PRECISION. 



1. Octagonal Planimeter, of the Florentine Tito Gonella, by Carl Starke, of 



Vienna (1852) ; an exquisite instrument. 



2. Three polar planimeters (1) from the Tecnomanasio of Milan ; (2) by 



Amsler-Laffon, of Schafhausen ; (3) by Ertel, of Monaco (1869). 



3. Planimeter, by Amsler-Laffon, of Schafhausen ; a very delicate instru- 



ment of recent invention (1873). 



4. Tychonic scale, designed by Giuseppe Pavan, of Padua (1874). 



5. Box compasses, by Montan, of Padua (1827). 



6. Crystal grating, by Merlo, of Milan (1870). 



7. Compass fitted by Montan, of Padua (1827). 



8. Calculating circle, constructed by Professor Legnazzi (1856). 



9. Calculating rule, Gravet-Lenoir (1860). 



10. Crystal grating, at the workshop of the Observatory of Padua (1849). 



11. Apparatus to graduate the small levels designed by Professor Legnazzi 



(1866). 



12. Box compass complete, by Toni, of Milan (1853). 



13. Box compass, by Bordogna, of Milan, a celebrated maker (1780). 



14. Ellipsograph, designed by Prof. Legnazzi, and constructed at the Royal 



Observatory of Padua in 1870. 



15. Compass of precision to take thicknesses. 



1 6. Compass of Bauernfeind, constructed by Mayer, of Dunkelsbiihl, which 



serves for the praetorian tablet (1871). 



17. Rule to draw a parallel at a given distance, by Rodella, of Padua (1819). 



18. Wide compass for drawings of precision (1872). 



19. Steel callipers with vernier (1870). 



20. Models of spikes with measuring wedges for the measurement of a base ; 



invented by Bessel, constructed by Ertel (1874). 



21. Models of rectilinear verniers for public instruction (1848). 



22. Ebony pantograph from the workshop of the Royal Observatory of 



Padua (1830). 



23. Rod Compass, by the distinguished mechanician Montan, of Padua 



(1824). 



GROUP VI. HYDRAULICS. 



1. Model of a careening basin, constructed 70 years ago. 



2. Model of a shell fitted in the Canale di Navigazione of Pavia ; designed 



by Leonardo da Vinci (1485). 



