149 
The Greenhouse. 
plants to be stood thereon occupy a position not too far from the glass. In 
a large span-roof it should take the form of a narrow ledge from two to three 
feet wide round the house. Next this a path two or more feet wide, with a 
flat stage in the centre. Small span-roof structures, say twelve feet by eight 
feet, should simply have a central path, the remainder being staging. In the 
case of lean-tos, unless very large, it is generally best to have the path at the 
back, and the staging in front. The reason for this is obvious to the practical 
mind; it enables the plants to be as near to the light as possible. Shelves 
are generally affixed to the back wall. In three-quarter spans there is more 
light at the back, and therefore the staging may be fixed against the wall, and 
the path be taken along the front. Of course, the exact position, as well as 
height and other dimensions, must 
be governed entirely by the size 
of the house. 
With reference to methods of 
heating, there are, of course, very 
many. The old-fashioned flues are 
quite out of date, being supplanted 
by the more efficacious and less 
troublesome forms of hot-water 
apparatus. Of the latter there are 
apparatus heated by oil, gas, and 
ordinary fuel. Those heated by 
oil and gas are, as mentioned in our 
remarks re heating the conservatory, 
very suitable for heating small structures. Their forms are legion, however, 
and we cannot, therefore, go into the details of their construction. A reference 
to one of the horticultural journals, say Amateur Gardening, will supply 
the names of manufacturers. Where the structures exceed, say twelve 
feet by eight feet, a Loughborough, Horseshoe, or Saddle boiler, heated by 
coal, cinders, or coke, will be more suitable than oil or gas. Hot-air stoves 
are also much used for small houses, but they are apt to render the atmosphere 
too dry for most plants, and hence cannot be recommended very strongly. 
The oil and gas apparatus are the most portable; the others require to be fixed 
in the ends of the houses. In a lean-to the piping should be arranged along 
the front and the end opposite the door, not along the back. In a span-roof, 
however, it should run along both sides and the two ends, with the exception 
Fig* 3 - 
