STAGING, BEDS, ETC. 87 
In many market nurseries the stages are constructed 
simply of ordinary flooring boards, 5in. or Gin. wide, 
laid on and lightly nailed to rough wooden uprights and 
cross-bearers, a space of din. or 3in. being allowed between 
each. This answers well—better on the whole than the 
narrow batten or lath staging, but with the objection 
that after a few years’ use the wood decays, and has to 
be replaced. If well painted before use, the wood 
naturally lasts much longer, but such preservatives as 
tar, creosote, and the ‘‘ black varnish” are inadmissible in 
the interior of plant houses, as already stated. 
Slate forms an admirable material for the surface of 
staging, being perfectly clean and sweet, as well as 
semi-porous, and a fair, but not too rapid, conductor of 
heat. Slate slabs of sufficient thickness. to sustain the 
weight of a number of pots (which, when full of moist 
earth, weigh more than many would credit), with that 
of a man occasionally, are, however, somewhat costly 
