92 MAINE AGRICULTURAL EXPERIMENT STATION. 



high winds. The ventilating sash should, if possible, be from 

 two to three feet wide and should be continuous for the whole 

 length of the house. 



There are several styles of ventilating apparatus, among the 

 more prominent of which are the Hippard, manufactured by 

 E. Hippard of Youngstown, Ohio; and the Challenge, manufac- 

 tured by the Quaker City Machine Company, Richmond, Ind. 

 The latter has been, perhaps, one of the most satisfactory with 

 us. Another style which we have in our houses is the so called 

 automatic cable ventilator manufactured by A. Q. Wolf & 

 Bro., Dayton, Ohio. This style has the merit of cheapness and 

 thus far has been very satisfactory with us. We have had it in 

 operation for three years. The Rochefort apparatus, now on 

 sale by Henry A. Dreer, Philadelphia, is an English machine 

 which acts on the same principle as that made by Wolf Bros. 

 This has been used but very little in this country. The auto- 

 matic ventilator, manufactured by the Chadbourne-Kennedy 

 Company, of Poughkeepsie, N. Y., is an expensive machine, 

 costing $50, but with us has proved very satisfactory. An 

 extended discussion need not be given in this connection 

 because it is not likely to be of general use among commercial 

 gardeners. In the extensive houses of W. K. Harris, Phila- 

 delphia, the machine is, however, exclusively employed and is 

 regarded very highly. 



6. Methods of Heating. 

 Whatever method of heating is used it is well first to con- 

 sider the cost, the efficiency, the durability and the economy 

 both of fuel and attendance. The method of conveying smoke 

 and other products of combustion through the house by means 

 of brick or tile flues has in the main been superseded by the 

 modern methods of steam and hot water heating. The first 

 cost of flues is certainly light and the fact that they are still 

 used by florists in many parts of the country is sufficient proof 

 of their efficiency, but they are not economical and there is 

 always danger of leakage and the escape of coal gas which is 

 very destructive to plant life. In the large lettuce houses which 

 supply the Chicago markets, however, this method of heating 

 is still very commonly used. 



