HENDERSON'S HANDBOOK OF PLANTS. 



366 



danger of the escape of gas from the I 

 flues into the green-house, which often j 

 happens when the draft is not active. I 

 Formerly the flues used to be run along | 

 one side or end of the green-house, emp- | 

 tying into a chimney placed there; but j 

 this method is rarely satisfactory, as the 

 cold outside air, rushing down the chim- 

 ney, throws back the heated air, particu- 

 larly in high winds, so as to nearly de- 

 stroy the heat; but by the method of 

 constructing the chimney on the top of 

 the arch of the furnace, and returning 

 the flue back into it, no such difficulty 

 can occur. 



Heating by Hot-Beds. The preparation of 

 the heating material for the hot-bed is a j 

 matter of importance. It should be 

 manure fresh from the horse-stable, and j 

 when they can be procured, it is better j 

 to mix it with about an equal bulk of j 

 leaves from the woods, or refuse hops. 

 If the weather is very cold, the bulk of 

 manure must be of good size, from five to 

 six wagon loads, thrown into a compact 

 round heap, else the mass may be so 

 chilled that heat will not generate. If a 

 shed is convenient, the manure may be 

 placed there, especially if the quantity is 

 small, to be protected from cold until 

 the heat begins to rise. The heap should 

 be turned and well broken up before be- 

 ing used for the hot-beds, so that the 

 rank steam may escape, and the manure 

 become of the proper ' ' sweetened " con- 

 dition. It is economy of the heating ma- j 

 terial to use a pit for the hot-bed. This 

 should be made from two to three feet i 

 deep, six feet wide, and of any required 

 length. After the heating material has j 

 been packed in the pit to the depth of j 

 twenty to twenty-four inches, according ; 

 to the purpose for which it is wanted, or j 



the season of the year, (the earlier in the 

 season, the deeper it is needed,) the sashes 

 should be placed on the frame, and kept 

 close until the heat generates in the hot- 

 bed, which will usually take twenty-four 

 hours. Now plunge a thermometer into 

 the manure, and if all is right it will in- 

 dicate 100 degrees or more; but this is 

 yet too hot as bottom heat for the growth 

 of seeds or plants, and a few days of de- 

 lay must be allowed until the thermome- 

 ter indicates a falling of eight or ten de- 

 grees, when the soil may be placed upon 

 the manure, and the seeds sown or 

 plants set out in the hot-bed. Amateurs 

 are apt to be impatient in the matter of 

 hot-beds, and often lose their first crop 

 by sowing or planting before the first vio- 

 lent heat has subsided. Another very 

 common mistake is in beginning too 

 early in the season. In the latitude of 

 New York nothing is gained by begin- 

 ning before the first week in March, and 

 the result will be very nearly as good if 

 not begun until a month later. There are 

 two or three important matters to bear 

 in mind in the use of hot-beds. It is in- 

 dispensable for safety to cover the glass 

 at night with shutters or mats until all 

 danger of frost is over; for it must be re- 

 membered that the contents of u hot- 

 bed are always tender, from being forced 

 so rapidly by the heat below, and that the 

 slightest frost will kill them. Again, 

 there is danger of overheating in the 

 daytime by a neglect to ventilate when 

 the sun is shining. As a general rule, it 

 will be safe in all the average days of 

 March, April, and May, to have the sash 

 of the hot-bed tilted up from an inch to 

 three inches at the back from 9 A.M to 4 

 P.M. Much will, of course, depend upon 

 the activity of the heating material in the 



