June 15, 1900.] 



SCIENCE. 



943 



stands suitable for investigators, from the 

 most prominent makers, and a full comple- 

 ment of objectives, immersion and apo- 

 chromatic. The outfit in question has 

 been planned to meet the habits and preju- 

 dices of workers from any part of the 

 country, and it has been found possible to 

 duplicate the apparatus to which any stu- 

 dent has become accustomed. 



The construction for special furniture for 

 the laboratories awaits the definition of the 

 forms most suitable for the character of the 

 work which may be undertaken here. 



A most interesting comparison with the 

 battery of modern high power optical ap- 

 paratus on hand, is afibrded by a collection 

 of old microscopes given by Mr. Chas. F. 

 Cox of the Board of Managers, which forms 

 a special laboratory exhibit. This collec- 

 tion illustrates the development of the mi- 

 croscope during the last century and a half. 



The physiological dark room opens from 

 the morphological laboratory, and is four- 

 teen feet square with double doors and in- 

 dependent ventilation, connecting directly 

 with the outside air. It is heated indi- 

 rectly by the walls of the contiguous rooms, 

 and its position in the middle of the wing 

 of the building together with its content of 

 over thirty-five hundred cubic feet of air 

 secure for it a verj'^ equable temperature. 

 This room has been in constant use for six 

 months including the period of tests of the 

 heating system of the building and the 

 total range of temperature has not ex- 

 ceeded four degrees centigrade, and at no 

 time has a variation of two degrees been 

 noted in a single week. The humidity 

 varies from sixty to eighty per cent, in the 

 work now in progress, and it has been found 

 to offer much more suitable conditions for 

 experimental work than any room used for 

 a similar purpose which has come under the 

 notice of the writer. 



A corridor leads from the morphological 

 laboratory to the class-room between the 



dark room and the ofiice of the director of 

 the laboratories (Professor's room, Fig. 4). 

 The class-room is thirty-five by twenty 

 feet, and one end is furnished with such 

 accessories as to make it suitable for the 

 weekly convention of workers from the lab- 

 oratories. The other end serves for the 

 private laboratory of the director of the 

 laboratories and contains the departmental 

 library. 



The physiological laboratory is a sky- 

 lighted room, thirty-five by thirty-two feet, 

 occupying the corner of the building. It 

 has a stone floor set in water-tight cement, 

 a tank for aquatics, and tables for cultures. 

 An ample heating surface is provided, and 

 a special system of steam pipes around un- 

 der the skylights secures ventilation, and 

 acts as a preventive of dripping moisture. 

 Ventilation of the ordinary type and that 

 of the greenhouse are provided, while a set 

 of shades may be used to cut off the direct 

 rays of the sun. By such means a range 

 of temperature similar to that of an inter- 

 mediate greenhouse is secured. To this 

 room are brought specimens from the plan- 

 tations and greenhouses for experimental 

 and observational purposes, and these are 

 removed as soon as the work with them is 

 finished. 



A small chemical laboratory opens from 

 the physiological laboratory, and leads into 

 the large chemical laboratory occupying 

 the corner of the wing. This room has 

 not yet been provided with the special fur- 

 niture and fittings necessary for chemical 

 work. It has a large ventilating hood 

 leading into a duct into which all the ven- 

 tilating flues of the room empty. A ven- 

 tilating fan driven by a powerful motor 

 is capable of renewing the entire body of 

 air in the room in a few minutes and thus 

 preventing the escape of noxious gases into 

 the contiguous laboratories. 



The second corner of the wing is occu- 

 pied by the photographic laboratory and 



