1072 SEC. 20. MISCELLANEOUS. 



accommodation for 50 workers, also ventilated by the main shaft; 2, metal 

 lurgical laboratory containing furnaces, also in connexion with the large 

 chimney; 3, store room; 4, class room ; 5, lavatory and cloak room; 6, 

 spectroscopic room ; 7, photographic room ; 8, dark room for photometry ; 

 9, boiler house ; and 10, preparation rooms. 



The first floor, Fig. 2, contains Professor Roscoe's private room, private 

 'balance room, and private laboratory with window opening into laboratories 

 Nos. 1 and 2. 



It will be seen from the plans that the block of working laboratories com- 

 municates by a corridor with the large chemical lecture theatre (capable of 

 seating an audience of 380), which has a small laboratory for the lecturer's 

 immediate use behind his platform. 



457 7a. Drawings of the Lecture Table in the Theatre of 

 the Royal College of Science, Dublin, erected under the direction 

 of Professor Barrett. Prof. W. F. Barrett. 



No. 1 represents the front elevation. 



" The shafting S, S, is divided into two parts, which can be thrown into one 

 by the clutch and handle H, H 1 . A belt passes round the large wheel E to 

 a three-cylinder water engine situated under the theatre seats ; another belt 

 passes round T to a turbine placed beside the water engine ; both engines are 

 surrounded by felt and packing to deaden their sound. Water is admitted to 

 the engines by means of the screw handles E 1 and T 1 , thus one or both halves 

 of the shaft can be simultaneously driven. The spindles of E 1 and T 1 pass 

 through the floor to the pipes below ; a hinged lid provides access to the cocks 

 below for oiling or repair. This lid, &c. also serves as a sloping foot-board 

 for the lecturer. 



Gas is laid on to every part of the table, and by means of the connections 

 and cocks G, G, flexible tubes can be attached. The peculiar construction of 

 these cocks enables them to be turned aside below the table when out of use, 

 or to be turned over the table when in use, thus preventing the kinking of the 

 flexible tubing. A large view of the cock is shown at G, Fig. 4. 



Oxygen is laid on to different parts of the table for the oxyhydrogen light, 

 or other purposes. One cock is seen at near the pneumatic trough, other 

 oxygen cocks are seen at O, O 1 , in Fig. 2. The supply is obtained from gas- 

 holders in the yard. 



Compressed coal gas or hydrogen in like manner is laid on from a gas- 

 holder and comes to the table through the pipes and cocks H, H, Fig. 2. 



Battery wires are laid on to the switch C, Fig. 1, a large view of which 

 is shown on the small diagram. By turning the handle of the switch from 

 10 to 50 cells or 1 to 5, can be thrown into circuit ; the binding screws for 

 wire attachments are seen at B, B, B. 



Water at high and low pressure is laid to the cocks at W, W", W", 

 &c. 



W is a large cock for screwing on hose, &c. 



W is a cock for filling pails, and by turning it outwards over the sunk 

 sink 2 the water flows, and is shut off by turning it back. 



W" is a small cock for filling small vessels. 



W" is a high pressure screw tap admitting water to a pillar screwed on 

 to W" in Fig. 2. 



"W 4 is a cock that turns water on to the pneumatic trough, and W a is a 

 screw cock that gives a supply of water to the other end of the table. 



A speaking tube P is laid on from the table to the battery and gasholders 

 in the yard. 



A, A 1 , are cupboards below the table, A for the purpose of keeping appa- 

 ratus dry and warm, A 1 under the pneumatic trough for a battery closet. In 



