tions of two houses which formerly were parallel. A house of this 

 width must necessarily be very high in the center, and a great deal 

 of space has to be heated which is of little use. 'J'his house con- 

 tains 42.800 cubic feet more than house No. 13. while the ground area 

 of house No. 13 exceeds that of house No. 12 by 5,200 square feet. 

 Since it is bed area and not cubic contents which constitutes the most 

 essential feature in a house devoted to the production of market 

 garden crops, house No. 12 is not an economical one. When houses 

 are constructed with one single even spanned roof, there is little to 

 be gained by having them over 40 or 50 feet wide. Market garden- 

 ers have usually realized this fact, and houses exceeding 40 feet in 

 width are very rare. The amount of coal burned in these various 

 houses also shows considerable variation. In all of these houses 

 hard coal is burned, except in houses 10 and 11. As far as we can 

 ascertain, however, there is little difference in expense between hard 

 coal and certain grades of soft coal, when the former is $7.00 per ton 

 and the latter $5.00. If hard instead of soft coal was burned in house 

 No 10, the coal per plant would be about 177 pounds instead of 250 

 pounds, there being little difference in cost. The amount of coal 

 burned in houses Nos. 12 and 13 cannot be obtained and the figures 

 for house No. 11 show the amount used in a lettuce house. The 

 variation in the amount of coal is not due so much to exposure, or 

 double roofing, or to differences in the temperature maintained, as 

 to the type of boiler employed, and economic piping and'firing. The 

 amount of coal burned per cubic foot in the larger and smaller 

 houses also differs. Unfortunately, however, data is not available 

 for houses Nos. 12 and 13. The single glazed house. No. 5, is 

 slightly higher in the amount of coal per cubic foot than most of the 

 double glazed houses, but is not so high as the double glazed houses 

 Nos. I and 8. The amount of coal* burned per plant is somewhat 

 misleading, as the plants in the houses are by no means under the 

 same conditions. 



For example, the first nine houses in the table are from 18 to it, 

 feet wide ; and while four rows of plants are set in them, they are 

 not capable of accommodating more than two rows. In double 

 glazed houses the light is so poor that the two middle rows are of 



*No attempt has been made to distinguish between the grades of coal burned. So far 

 as we are aware Httle difference exists in this respect. 



