38 
BULLETIN 510, U. S. DEPARTMENT OF AGRICULTURE. 
WOOD PRESERVATIVES IN THE LUMBERYARD. 
Aside from the advisability of preserving permanent structures in 
the lumberyard by the use of antiseptics applied to or injected into 
the wood, the question of preserving the lumber itself from incipient 
infection until it reaches the consumer is one which merits careful 
thought. During the past decade the use of soda (sodium carbonate 
or bicarbonate) dips to prevent blue stain has become general 
throughout the southern pine belt. Within the writer's own experi- 
ence, sawmill men who in 1909 scoffed at such a measure had within 
three or four years fallen in with the procession and were enthu- 
siastic advocates of it. As yet the idea of dipping the lumber to 
prevent infection from true wood-rotting fungi has not been con- 
sidered by the lumber- 
men. The soda dip is 
not sufficient to accom- 
plish the desired end, 
so we must look else- 
where for a suitable 
preservative. Mercuric 
chlorid is a hazardous 
thing to use on general 
stock, on account of its 
extremely poisonous 
nature, but is very effi- 
cient and safe enough 
for special purposes. 
Zinc chloric! is objec- 
tionable mainly on ac- 
pio2F count of its capacity to 
Fig. 39. — Broken foundations, a result brought about . r\£ 
by not reinforcing the concrete. The company later attract moisture. Kjl 
embedded some old 20-pound steel rails in the con- ^]^ e remaining Colorless 
crete near the top. . to „ 
salts in use tor wood 
preservation sodium fluorid or some colorless salt of hydrofluoric 
acid would probably meet the needs of the situation very well. So- 
dium fluorid is highly toxic to fungi, but can be handled by workmen 
with no danger of poisoning. It is colorless, easily soluble, and can 
be handled in any way that the soda dip can. It is more effective 
than soda and so could readily be substituted for it, thus protecting 
against both the blue stain and the wood-rotting fungi by a single 
treatment. 
This whole feature of dipping lumber in. this way to keep it in 
a clean condition for the consumer must necessarily involve the 
close cooperation of millmen, Avholesale men, and retailers. The 
millman may feel indifferent to the proposition, claiming that the de- 
