898 SEC. 20. COLLECTION OF APPARATUS AND PHOTOGRAPHS 



4564. Photographs of Scientific Instruments in the Phy- 

 sical Cabinet of Science, University of Pavia. 



Director, Prof. Giovanni Cantoni. 



1. Small apparatus for the study of reciprocal electrical influence, with two 

 electrometers. Volta. 



2. Two electrophori which recharge themselves and work as unfailing sources 

 of electricity (first example of an electric machine by induction). Volta. 



3. Measurer of powerful electric tension, hy Volta. 



4. Apparatus for the study of the electric spark. Volta. 



5. Apparatus for the dilatation of gaseous fluids. Volta. 



6. Electric duplicator hy Giuseppe Belli. (Attempt at an electric multiplier 

 which served to introduce the next machine.) 



7. Electric machine hy induction, G. Belli. (First example of an electro- 

 meter by induction, somewhat like the first machine of Holtz). 



8. Hygrometer, with durable indications (by the same). 



9. Psychrometer with bellows (by the same). 



10. Collector of atmospheric heat, with continuous indications, by Con. 

 Bellani. 



11. Psychrometer with continuous indications, by Con. Bellaui. 



12. Balance barometer, modified by Prof. Giovanni Cantoni. 



13. Normal barometer for Meteorological Stations, by Prof. Giovanni 

 Cantoni. 



14. Psychrometer with ventilator, by Prof. Giovanni Cantoni. 



15. Electric balance, by Prof. Giovanni Cantoni. 



16. Electric scale, for the measurement of electrical adherence. 



17. Maximum and minimum thermometer, by Prof. Giovanni Cantoni. 



18. Anemometrograph, by Prof. Parnisetti and Ferd. Brusotti. 



19. Modification of the machine of Attwood, by Ferdinand Brusotti. 



20. Hygrometer worked with sulphuric acid, improved by Brusotti. 



4565. Photographs of Scientific Instruments in the 

 Royal Observatory of Palermo. Director, Prof. G. Cacciatore. 



1. Great circle by Rainsden, 1790. The principal parts are, first, a vertical 

 axis of conies, parallelepiped form, destined to support two graduated 

 circles, one for altitude, the other for azimuth. 2nd. The upper support of 

 this axis, formed of four columns with four arches, and a collar in the middle. 

 3rd. The lower support, composed of three circles placed horizontally one 

 on the other. 4th. A balustrade. 5th. An achromatic telescope. 6th. Three 

 microscopic micrometers, with other smaller pieces. (See annexed description 

 by Piazzi.) 



2. Catalogue of the stars made by circle No. 1. 



3. Equatorial, by Merz. (Aperture of object glass 9-665 inches.) Set up 

 in 1865. 



4. Spectroscopic observations by the above equatorial. 



5. Seismograph of Niccolo Cacciatore, 1826. A circular receiver, per- 

 forated laterally in eight parts, indicating the four cardinal points, and the 

 intermediate points. Placed on a perfectly horizontal plane, and filled with 

 mercury which touches the holes, and which therefore can spill at the least 

 oscillation, and in the direction of the oscillation. A corresponding number 

 of small cups placed below the holes to receive the spilt mercury, which 

 may afterwards be replaced. The mercury received in the cups indicates the 

 undulatory shocks of earthquake. 



6. Anemometer by Niccolo Cacciatore, 1832. Attached is a description of 

 the instrument by the inventor. 



