VARIETIES. 625 



Tlrese moveable points the Professor thinks the house might require. The original 

 can be nothing else than the clouds in the floor had not been moved, hut at a short 

 moon's atmosphere. distance heneath it a second floor had been 



London Mechanics' Institution. It formed , in which were between twenty and 

 appears from the paper handed in by Mr. thirty large apertures of about eighteen 

 Toplis, to the Commons' Committee on inches in diameter. Through these aper- 

 Arts and Manufactures, that it has no less tures the cool or heated air was in the first 

 than 4070 members, each contributing instance admitted, and immediately over 

 yearly \l. 4s. The library contains upwards them were placed large platforms sustained 

 of 6000 volumes, and its collections of mi- by short feet, which had the effect of dis- 

 neralogy, geology, &c., are both extensive persing the great body of air which the 

 and valuable. The philosophical appa- large apertures admit. The air then enters 

 ratus is one of the best in the metropolis, through perforations made in the actual 

 Eleven evening classes are constantly floor of the house perforations to the al- 

 maintained, on English, arithmetic, mathe- most incredible number of 350,000. These 

 matics, practical geometry, drawing, mo- lesser apertures are about the sixth of 

 delling, French, Latin, &c. The greatest an inch in diameter. These are the means 

 number of class-members in any one class provided for the ingress of the fresh air. 

 is seventy-three, the smallest twenty. A Its egress is provided for by means of each 

 class of music (extra) boasts of ninety panel of the centre compartment of the 

 members. Away then with the drivellers ceiling being raised by blocks several 

 who affect to despise the "great unwashed." inches above their 'styles.' The next 

 We question whether many members of difficulty to overcome was the promotion 

 the legislature could compete in talent and of such a circulation as would pump out 

 intelligence with the sensible mechanics of with rapidity foul air and introduce fresh, 

 this institution. and this object the professor effected in the 



Improved Method of Ventilating the following manner. A large circular shaft 

 House of Commons. Extensive altera- erected at a distance of about 20 feet from 

 tions have been for some time going on, the eastern wall of the building, was con- 

 under the direction of Dr. Reid of Edin- structed so as to contain at an elevation of 

 burgh, with a view to the improved ven- 10 feet from the surface of the earth an 

 tilation and transmission of sound. It exceedingly large coal-fire, the operation 

 may interest the reader to read the follow- of which is to rarefy the air within the 

 ing report of the experiments tried at the shaft, a portion of which below the fire has 

 House of Commons : a communication with a square shaft in 



" The trial was made with the house immediate contact with the house, and is 

 filled by individuals to an extent exceed- continued to the space above the inner 

 ing the usual number of members in at- ceiling. The result of these arrangements 

 tendance at a time, and accordingly, at wr.s, that when the air in the circular shaft 

 three o'clock, drafts from the foot-guards became intensely heated, and, therefore, 

 were marched down from their barracks exceedingly rarefied, there would be pro- 

 and placed seated in the body and galleries duced a downward draft through the square 

 of the honse. Their number, with the offi- shaft, and the effect of that operation would 

 cers in command, amounted to 412, and of be the rapid withdrawal of the air within 

 the civilians present, the total was as- the house and the substitution of fresh air 

 certained by a ' division ' at the close of for foul. The action of both shafts was 

 the experiments we are about to describe, of course regulated by dampers, 

 to be exactly 128, so that the ' house' may Several experiments were made by Dr. 

 be said to have consisted of the unusual Reid, which triumphantly proved the suc- 

 number of 540 'members.' Dr. Reid cess of his plans so far as regards ventila- 

 stated that the main object was to intro- tion. Of his acoustic improvements we 

 duce imperceptibly a vast body of fresh hesitate to speak until we shall ascertain 

 air, either cool or heated, as the state of their practical results at the opening of 

 the weather or the number of members in the Session. 



