94 



FIELD TRIPS OF THE CLUB 



Trip to Mistaire Laboratories, Millburn, N. J., 

 February 7, 1942 



About twenty members and guests of the Club met at Mistaire 

 Laboratories, in spite of a rainy afternoon. They observed the unique 

 laboratory and greenhouse, where an attempt is made to control all 

 factors of plant growth while using natural daylight. Special exhibits 

 were arranged to explain the research and the methods used in rais- 

 ing ferns, orchids, and other plants. 



All plants are started with exceedingly careful pure culture tech- 

 nique on nutrient agar of known composition within glass containers. 

 Among the exhibits in the planting room was a vibrator, used to 

 shake the seeds or spores being sterilized. Prothallia were trans- 

 planted from one tube to another with a platinum needle over a 

 flame. Flaming stoppers were snuffed out under a copper cone at- 

 tached to a standard. A 'practical method for siphoning sterilized 

 solution from a large flask into hundreds of older tubes, in order to 

 adjust acidity and moisture, was shown. The air conditioning system 

 was so regulated that the pressure within the planting room was 

 greater than in the laboratory or outdoors. This kept unwanted germ 

 laden air from entering through cracks. 



Growth and development of the plants is governed by automatic 

 controls of humidity, temperature, and light in the greenhouse. A 

 humidistat controls two humidifiers. Vaporized cold water is used 

 because it is more beneficial to living organisms than humidity 

 formed by heating. The temperature in the greenhouse is kept be- 

 tween 70° and 80° F. by means of an electric thermostat. If extremes 

 of 65° and 85° F. occur, an auxilliary thermostat causes a warning 

 bell to ring in the house. The temperature is also controlled by an 

 outer layer of Solex glass which eliminates most of the infra-red or 

 heat rays of the sun, and acts as an additional insulation in winter. 

 Summer heat thermostatically regulates a fine spray of water be- 

 tween the two layers of glass. Automatic recording instruments make 

 permanent graphs of temperature and humidity. 



Within the greenhouse, nine photo-electric cells were function- 

 ing. One automatically controlled a large shade ; the second, the day- 

 light and green fluorescent lights ; the third and fourth, the light 

 recording meter ; others were for general study of light intensity. 



