102 
HOUSEHOLD BACTERIOLOGY 
Bed-making 
tion when dusting should be done, if the aim of dust¬ 
ing be to remove dust from the house. If, then, these 
and other experiments have shown that at least two 
hours are required to free the air of a still room from 
the bacteria present in its dust, it is of little use to 
dust immediately after sweeping. When this is done, 
no wonder the housewife exclaims in despair, “Why, 
this room was dusted this morning, but you never 
would have known it!” 
While we cannot always let two hours elapse be¬ 
tween some dust-spreading process of housework, like 
sweeping or bedmaking, we can remember that the 
raised dust must settle before we can remove it. Wait 
as long as possible! 
When Fig. 46 is compared with Fig. 47, the reason 
is plainly seen why rugs mean less dust than carpets 
and therefore a cleaner, healthier house, because these 
can be carefully rolled, cleaned out of doors, and the 
floor wiped with a damp cloth. 
Next to sweeping as a dust-raising and dust-spread¬ 
ing process comes bed-making. 
Fig. 48 shows a plate planted just after a bed had 
been made. The colonies of bacteria and molds in this 
plate had been growing for a longer time when the 
photograph was taken than in plates Fig. 46 and Fig. 
47. Two of the molds on this plate are very mature, 
being black with spores. 
As health requires that the air of the sleeping room 
be as free from dust as possible, considerable time 
