896 SEC. 20. COLLECTION OF APPARATUS AND PHOTOGRAPHS 



3. Lantern for electric light, with Foucault's regulator, con- 

 structed by Duboscq.* 



4. Lamp for oxyhydrogen magnetic light, by Carlevaris. 



5. Lamp for the Drummond light. 



6. Regulator for electric light, by Archereau, with reflectors, 

 invented by Prof. Rossetti so as to throw the light in all directions. 



(14.) 1. COMPLETE OPTICAL BANK. 



2. Microscope, by Hartnack. 



3. Microscope, by Amici. 



4. Microscope, by Plossl. 



5. Dialytic telescope, by Plossl. 



6. " Lentiprisma." 



7. Prism for projections. 



8. Spectroscope, for direct vision. 



9. Bunsen's Spectroscope. 



(15.) 1. Large APPARATUS for POLARISATION, made by SoleiL 



2. Apparatus by Norremberg. 



3. Apparatus for polarisation, Biot. 



4. Apparatus for polarisation, Arago. 



5. Cianopolarimeter, Arago. 



6. Apparatus for polarisation, by Mams. 



7. Saccharometer, by Soleil. 



8. Phosphoroscope, by Becquerel. 



(16.) 1. ATMOSPHERIC THERMOMETER, by Jolly, made at Monaco. 



2. Apparatus by Clement and Desormes. 



3. Mercury calorimeter, by Favre and Silbermann. 



4. Complete apparatus of Melloni, made by Ruhmkorff. 



(17.) Working model of stationary STEAM ENGINE. 



(18.) 1. COMPASS, by Prazmowsky, for measuring the intensity 

 of the horizontal components of terrestrial magnetism. 



2. Compass for decimation. 



3. Magnetic theodolite, of Lament, made at Monaco. This 

 instrument is portable, and serves to determine all the magnetic 

 constants. 



4. Apparatus, Faraday's, for diamagnetism. 



(19.) 1. Large ELECTRIC MACHINE, by Winter, with two discs. 

 Made at Vienna. 



2. Machine, Holtz's, of the second kind, with horizontal discs. 

 Made at the Tecnomanasi of Milan. 



3. Double machine, PoggendorfPs. Made at Berlin. 



(20.) HOLTZ'S MACHINE, of the first kind, worked by a wheel. 



It was used in this way by Prof. Rossetti to measure the amount of work 

 employed to produce a current of given intensity, and for other experiments 

 described in his memoir " Nuovi Studii sulle Correnti delle Macchine Elettriche " 



* To this is attached a projection microscope. 



