CONSTRUCTION AND HEATING OF GLASS HOUSES. 63 



It is the lack of a thorough knowledge of these conditions with 

 builders and architects in general, that is responsible for the 

 thousands of greenhouses throughout the country which are 

 practically useless for the purposes for which they wei'e built, and 

 has thus caused loss of interest in plant culture, in addition to the 

 loss of dollars, to those who otherwise undoubted!}^ would have 

 been the means of materially furthering the interest of the public 

 in matters horticultural, and consequently would have helped to 

 create a greater demand for the products of our commercial 

 growers. I mention these facts just here in order to emphasize 

 the advisability and necessity when building glass houses, of first 

 making yourself acquainted with the most perfect methods of 

 construction ; and without question, the easiest, quickest, cheapest, 

 and in every way the most satisfactory means of doing this is to 

 consult some prominent and progressive firm of horticultural 

 architects and builders — men whose whole thought and energy 

 are bent in this particular direction. 



The details for a perfect iron frame for a commercial house maj' 

 be seen by Fig. 2. It will be noticed that for the foundation a 

 cast iron post base is used, which may be made of any desired 

 length, according to the nature of the ground upon which the 

 house is to be built. The post bases are usually about two feet, 

 six inches long, and are set into the ground to their full depth, the 

 tops being about on the level of the floor-line of the house. To 

 this base is bolted an iron post, the post in this instance being that 

 used by Messrs. Hitchings & Co. in their improved patented con- 

 struction. Other styles of iron posts may be used, such as the 

 ordinary angle or T iron of commerce, but care must be taken to 

 select them of such a shape and of such dimensions as will not 

 only support the dead weight of the house but also have no 

 tendency to warp, sag, or twist, in case of strains being brought 

 to bear in other directions than vertically as above stated. The 

 advantage of the cast iron post, in addition to being designed 

 with a view to convenience of attaching other parts of the frame 

 to it, is its great stiffness, strength, and general adaptability. 



"We will now pass to the rafters. I ' find in general practice 

 when a suitable bracket is used for connection of rafter and post, 

 and of rafters to each other at the ridge, that where the length 

 does not exceed seven feet between supports, (except in the case 

 of grapery roofs) a section of flat iron two inches by one-half 



