New York Agricultural Experiment Station. 339 



The watering was usually (lone early enough in the day to 

 have the atmosphere dry at night. On bright days the atmos- 

 phere was made moist by wetting the walks and floors, and the 

 plants were syringed lightly if they showed a tendency to wilt. 



ventilation and temperature. 



The ventilation was managed so as to avoid cold draughts 

 and sudden changes in temperature. The greatest care was 

 required to prevent tipburn after the plants began to head. On 

 a bright day following a period of dull dark weather the temper- 

 ature was constantly watched and especial care taken to hold 

 it nearly as low as it had been on the dark days and at the 

 same time the atmosphere was kept moist by following the 

 method above described. 



The night temperature was kept between 45° and 55°; the 

 day temperature from 60° to 65° in dull weather, but on sunny 

 days it was allowed to run up to 70°. During the period of 

 germination and also just before the plants matured 'he temper- 

 mature was kept somewhat lower than it was during the season of 

 more active growth. 



harvesting the crop. 



The crop was not cut till the earliest-maturing heads had fully 

 developed into prime marketable condition. Then the whole 

 crop was cut. The loose lettuce and head lettuce were not cut 

 at the same time, however, because the crops did not mature 

 at the same time. In 1890-00 the head lettuce M'as cut about 

 two weeks before it would have matured, as explained in the 

 notes for that crop. 



Each head was weighed as soon as it was cut, before it had a 

 chance to lose weight by evaporation. Full records were made 

 of the character of the plant, including its weight. The limits 

 of this report will not permit the publication of all these data, 

 but so much of them is given as appears necessary to establish 

 the facts brought out by the investigation. 



