HEATING GREENHOUSES 93 



low pressure system you have the same pressure on the boiler as you 

 have on the pipes in the houses, five, ten or fifteen pounds, which is 

 about the average pressure on the pipes, either high or low pressure used. 



To use the high pressure you must put in a reducing valve on the 

 main feed pipe whereby you can carry forty to fifty pounds or more on the 

 boiler, then set the valve to the number of pounds you desire in the 

 houses. Of course, under the high pressure system you must have a 

 trap system, in connection to return the condensed water. The high 

 pressure system is greatly recommended as a saving in heating; it heats 

 the steam to a greater degree of heat, and thus when it gets into the 

 pipes it is more hot air and not as much water, as in the low pressure. 



The amount of coal it takes, I find on an average, on a range of 

 houses, of roses, carnation house plant, and down to violet, say fifty thou- 

 sand feet, is 175 tons per month at a cost of about $500.00 or three and 

 a half tons of coal to every thousand feet of glass, at a cost of $10.00 per 

 thousand feet of glass, or $1.00 per hundred, or one cent per foot, per 

 month. I am basing these prices on Cherokee steam coal at an average 

 cost of $3.00 per ton. 



The fireman is the man that can save your firm 50 to 100 per cent on. 

 the price of heating if he understands his business. He is the man who 

 can give 3'ou the mildew on your roses or a lot of other things, if he does 

 not keep the temperature at an even point, or goes to sleep and lets you 

 freeze out. 



If he understands his business in keeping the boilers clean with a 

 good boiler compound and well washed out, keeps his grates clean, free 

 from clinkers, and always a fine bright fire, if he is a man that tries to 

 see how much heat he can get out of the least amount of coal, and not 

 a man that tries to see how much coal he can burn during the night, he 

 is a man that will be invaluable to you. 



When you are through firing in the spring, and shut up your boilers 

 put in some good boiler compound and fill up your boilers with water and 

 they will keep a great deal longer than if you empty them and let the 

 air get into them, which will rust them a great deal quicker than the wa- 

 ter will. Then early in the fall clean them out thoroughly, inspect them 

 good with a hammer test, and go over the brick work, and they will then 

 be ready for another seven to nine months' service. 



There are many other things connected with the heating system that 

 I did not mention such as a temperature man, who ought to be an expert 

 florist to look after the proper heat, and ventilation at night. Also the 

 smoke consumers, combustion chambers, fans, or artificial drafts, which 

 my limited time does not permit me to go into detail about, will force me 

 to leave those things with you for discussion. 



DISCUSSION. 



Mr. Williams: I realize that our time is getting short, but there is 

 a paper that I have been trying to have some one present for several years, 

 and I am the one that suggested that paper being read at this meeting. I 



