128 
THE YOUNG SCIENTIST. 
ferent degrees of ellipticity, this ring is 
moved from a given point. To work this 
chuck a slow motion must in all cases be 
used, in order to stay the vibration that is 
otherwise caused by the oscillation of the 
slide of the chuck. To determine the dif- 
ference between the major and minor axis 
of the ellipse is a simple matter. For in- 
stance, if the ring is moved I in. from the 
centre, the difference will be just h in. 
This gives an example, and it must be 
clearly seen the ellipse is exactly twice 
the size one way to what it is the other. 
Many beautiful patterns may be executed 
with this chuck, by dividing with the 
wheel that is on the front of it. In divid- 
ing with this instrument it must be ob- 
vious to all that the division must take 
place on the wheel, as the mandrel must 
necessarily revolve with the action of the 
chuck. A few practical lessons or hints 
on this tool will soon enable a complete 
novice to overcome its difficulties. When 
the use of this chuck, to a certain extent, 
is mastered, and another addition is re- 
quired, we should recommend as the best 
an eccentric chuck, because the combina- 
tion of the oval and eccentric produce 
some very beautiful work. The latter, 
when used with the former, should be 
fitted with a transfer chuck ; it will then 
run true on its place. In continuing to 
give an account of the various additions to 
be made to an ornamental turning lathe, 
we do not wish our readers to labor under 
the impression that all the various things 
we name are absolute necessaries, but, 
from a long experience, we feel enabled to 
advise the best means of proceeding, if it 
be the wish to do so; though, before 
making any further purchases, be certain 
that you know the use of that which you 
already have. The dome chuck will be 
found the next most useful addition, as 
some very pretty work can be done with 
it, and to a very limited extent it takes the 
place of the spherical slide-rest. This 
chuck may be worked in conjunction with 
the oval and eccentric, and most curious 
results obtained. One of its principal uses 
will be to cut square or hexagon bases ; 
with the slide-rest set to the surface, this 
kind of work may be done in various ways. 
Some prefer one, some another. 
In proceeding with additions to the 
lathe, a drill-spindle, with a set of large 
moulding-drills, will be found a very | 
useful thing to have ; this also enables the i 
turner to produce some very elaborate 
work with very little trouble. Passing ' 
again to chucks ; the geometric chuck is 
one that to some turners gives a deal of 
satisfaction, and it certainly is a most , 
beautiful tool ; but, at the same time, it \ 
does little more than what the chuck I 
does, leaving little scope for the the opera- : 
tor's powers of design. We prefer to see j 
some of the beautiful tazzas, vases, etc., ] 
that are done by some of our readers, who , 
excel in the use of the more simple chucks 
and cutters. When we come to all these j 
expensive additions, naturally a large ex- j 
penditure is necessary, but it is not at all ji 
necessary to spend a large sum to produce 
some fine work. 

Science in Common-place Things. 
TT is an old proverb that a man cannot 
raise himself by pulling on the straps 
of his boots. Something almost as won- 
derful can be done however : A man can 
easily raise himself by the pressure of 
his own breath, and if time were given 
him, it would not be impossible for a man 
to raise himself to the top of a house by 
this means. How it may be done we may 
explain in a future number, but in the 
meantime we will tell our readers how to 
perform an experiment almost as wonder- 
ful, and that is, to blow an egg out of one 
wine glass into another. Now an egg is a 
tolerably solid affair, weighing on the 
average about two ounces. If we were to 
attempt to blow it about, or support it in 
the current of air propelled from the 
mouth, we would probably fail, but if we 
proceed as follows, success is almost cer- 
tain after a few trials. 
Get an egg, and lest it should fall and 
make a mess, it is well to have it hard 
boiled. Then select two wine glasses in 
which the egg will nicely fit, (or if you 
have the glasses you may select the egg- 
either way will do), and place the two 
wine glasses as shown in the figure, but | 
rather closer together, as it will be found 
difficult to send the egg as far as the dis- \ 
