THE YOUNG SCIENTIST. 
31 
from the British Museum to work upon ! 
But these facts are not inconsistent with 
the other fact that WoUaston owned and 
used large quantities of very powerful ap- 
paratus. The great point in WoUaston's 
methods, and that which the student 
ought to try to imitate, is the proper 
adaptation of means to ends. 
Science of Common Things— Inertia. 
NOTHING serves so well to explain any 
great law as numerous illustrations of 
it under varying conditions. We there- 
fore give our readers another experiment, 
which illustrates the same principle as 
that involved in the experiment with the 
wooden ball, detailed in our last number. 
We have here a pile of draughts, and the 
problem is to knock out one of the lower 
ones without disturbing the rest of the 
pile. It is easily done by striking one of 
of the draughts, the pile will topple over. 
If the stroke should be at all upward, the 
upper draughts will be raised and knocked 
about. The experiment may be varied by 
placing a card on the tip of the finger and 
a quarter dollar on the card. A smart 
blow on the edge of the card will drive it 
from beneath the coin, and leave the latter 
poised on the end of the linger. 
A Strategic Wasp. 
VrOT long since, while readii;ig beneath 
the shade of a fig tree, our attention 
was attracted by a peculiar loud and 
shrill buzzing sound, as of some one of 
the bee family in distress. Looking In 
the direction of the noise, we observed 
quite close to us a dirtdauber, or builder, 
one of the species of wasps so well known 
for the cylindrical cases of mud it builds 
under eaves and on sheltered walls, which 
EXPERIMENT ON INEETIA. 
the draughts a sharp blow with some thin 
strip of wood, ivory, or metal. A table 
knife answers very well— the stroke being- 
given with the back and not with the edge. 
The special point in regard to which care 
is to be exercised, is that the stroke be 
quick and level. If we merely push one 
it stuffs full of certain worms and spiders 
for its young. This wasp had half of its 
body and head down the hole of the 
equally well-known doodlebug, a worm 
which children pull out of their holes by 
teasing them with a straw until they 
grasp it with their strong nippers, and 
