intervals diirino- the winter, the results of which are given in the 

 following table. Four observations were made each day. 



Table No. 3. 

 east house. west house. 



North Section. South Skctiox. Noktii Section. South Section. 



Av. temp. Av. temp. Av. temj). Av. temp. Av. temp. Av. temp. Av. temp. Av. temp, 

 over under over under over under over under 



bench. bench. bench. l)ench. bench. bench. bench. bench. 



Week ending January 31, 1891. 

 63.89 84.23 60.75 60.46 



"Week ending February 7, 1891. 

 49.39 48.83 49.39 36.10 



Weeks ending March 14 and 21, 1891. 

 65.27 64.30 62.85 59.90 



67.53 67.35 64.08 59.85 



Two -weeks ending April 6, 1891. 

 56.89 53.31 55.87 50.93 



In this ease the difference in the temperature between the space 

 under the benches and that over them is much more marked in the 

 west house than in the east, showing that when the pipes are arranged 

 over the benches the heat is not so evenly distributed through the 

 houses as where ari-anged under the benches. 



SPECIAL FERTILIZERS FOR PLANTS UNDER CiLASS. 



During the winter of 1889 and 1890, experiments were made with 

 fertilizers applied to crops under glass, the results of whicli were 

 given in Bulletin No. 10. The past winter the same experiments 

 were repeated. For this purpose six plots were arranged in each of 

 the two greenhouses used for testing systems for greenhouse heating, 

 and planted about Sept. 20th, with the same kinds and number of 

 carnations. 



The number of blossoms produced by each plot was recorded as 

 described in the experiment for testing systems of piping. Each 

 plot had api)lied to the soil, soon after planting, one of the elements 

 of plant food in the form used in the common commercial fertilizers. 

 The greatest care was taken that the soil, watering, ventihilion and 

 all other conditions should be the same. 



