MISCELLANEOUS. 1073 



.Fig. 5 this cupboard is shown open ; X is a draught pipe leading to a flue at 

 the back of the lecture theatre. 



In Fig. 5 is also shown the manner of opening the lid of the pneumatic 

 trough ; the slide V rests on the solid brass pillar Y, which is hinged at its 

 upper end to the table. 



No. 2 shows the surface of the table. 



The pneumatic trough is seen open. X 1 is a down draught pipe to carry 

 off noxious gases. 



X 11 is another down draught at the right hand of the lecturer. These 

 draught holes are closed by round lids, over which is a square well-fitting 

 block. When all the openings are closed the top ef the table presents a 

 solid unbroken surface. 



K is a slide that can be removed entirely to alloAv of free access to the lamp 

 which stands on a swivel table, as shown in Fig. 3. 



U, U 1 , are brass collars wherein fit, by means of a bayonet joint, sliding 

 brass arms, one of which is shown in Fig. 3. 



I is an aperture (that can be closed by the lid I 1 ) to allow a belt to pass 

 from the shafting on to the table. 



Fig. 3 gives a perspective view of the table, with some apparatus placed 

 on it to show the use of some of the fittings. 



4578, Plan of the Laboratory of Physics of the Im- 

 perial University of St. Petersburg, with an index of its 

 sections. Imperial University, St. Petersburg,. 



In the plan of the room devoted to the experiments of students, there is 

 indicated the arrangement of the several groups of apparatus required for 

 demonstration. A complementary description written separately contains a 

 short sketch of the experimental problems that are successfully laid before 

 the students during their first year's experimental studies. 



PHOTOGRAPHS. 



4556. Photographs of Scientific Instruments in the 



Institute of Physical Science, Royal University of Rome. 



Director, Prof. B laser na. 



1 . Balance of precision made by the mechanician Scateni, of Urbino ; the 

 suspension very simple and excellent. With a weight of kilogram 2 per 

 scale. Indicates to -| milligramme. 



2. Universal wheef, made in the workshop of Galileo, in Florence. It 

 alloAvs rotary motion to be produced in cylinders and discs in horizontal and 

 vertical directions with the most different velocities. 



3. Scott's Phon autograph, made by the machinist De Palina, of Naples. 

 The writing lever has a special arrangement devised by Mr. Campbell, lecturer 

 at the Physical Science Institute, by which it rests only upon the centre of the 

 vibrating membrane, while the other support transforms the vibrations into 

 movements parallel to the axis of the rotating cylinder. 



4. Instruments of precision, made by Starke and Kaumerer, of Vienna : 

 (A.) Complete theodolite ; horizontal and vertical circle, which permits, by 

 the aid of microscopes with a movable ocular thread, to read up to \". 

 (B.) Apparatus for the measurement of the indices of refraction. For the 

 reading are added two microscopes with movable ocular threads, allowing a 

 direct reading of 1". Repeating movement, with excellent arrangement of the 



40075. 3 Y 



