March ii, 1892.] 



SCIENCE. 



143 



related we may judge by what was said above, but there are 

 reasons for believing them to differ from each other as they 

 both differ from heat, although all alike are forms of energy. 

 Actinic absorption, like coloric absorption, is attended with 

 decomposition, but so far as the former is attended with or 

 followed by an aggregation or combination of elements, as 

 with chemical affinity, it is also a force, but molar rather 

 than molecular or atomic. In distinguishing between these 

 forms of matter, I adopt the principle laid down by Mr. 

 Grant Allen, although not all the applications he makes of 



ogy at the instance of the writer. A suite of rooms, of which 

 the accompanying cut gives the dimensions and arrange- 

 ment, was set apart for the use of this department. The 

 laboratory is located at the west end of the restored Univer- 

 sity College building on the first (not the ground) floor. It 

 is isolated entirely from the general work of the building, 

 being over the rooms of the physical department. The rooms 

 have light exposure from three sides. The room which is 

 used for students' demonstration and practical work (I. in 

 the plan) is cut off from the research rooms, thus making 



A, A, A, Windows. 

 DemonstratiDg-room and work-room for undergraduates. G, Work-table; E. Book-cases; K. Black- 

 board; F. Demonstration-table; e'. Students^ entrance; e. Professor's entrance. 

 Research-room. M, N. Work-tables; B, C. Lockers, movable incandescent lights; I. Chart-case, 



movable tables; R. lostrument-cases. 

 Professor's Research-room. O. Work-table; D. Book-cases; H. Closet for tools, &c ; L. Movable 



incandescent light, lockers; S. Writing-desk. 

 Dark-room. W. Sink; V. Vestibule; P. Incandescent light. 

 Private hall. X. Stairs; e. Professor's entrance; Y. Instrument-cases. 



them, and I believe that in the recognition of the truth of 

 those principles will be found the solution of many scientific 

 problems. ' C. Staniland Wake. 



THE PSYCHOLOGICAL LABORATOEY IN THE UNI- 



VEESITY OF TORONTO.' 



In the spring of 1891 an appropriation of $1,100 was made 

 for the equipment of a laboratory for experimental psychol- 



^ The accompanying plan is published at the suggestion of several psy- 

 chologists who have borrowed and examined It; it Is ihought that the details 

 may be of use to professors, boards, or trustees who are contemplating the 

 providing of laboratories. 



interruptions to the latter from noise, etc., unlikely. For 

 the same reason, the central hall is laid with cocoa matting. 

 The work-tables of the research rooms (II. and III.) get light 

 from the east, south, and west, a variety which is of great 

 value, especially as the east exposure (Room III.) has re- 

 flected light from the walls of the main building (this is also 

 partly the case with the light from the west windows. Rooms 

 I. and II.). The rooms are artificially lighted by combina- 

 tion gas and electric chandeliers from the ceilings, and have 

 besides movable incandescent lamps over the work-tables. 

 The dark room is also furnished with incandescent lights. 

 The floors throughout are carefully laid in hard wood. The 



