134 
THE YOUNG SCIENTIST. 
have it well rubbed in on the ends. He 
explained to them that the oil would pre- 
vent the planes from checking, and render 
them less liable to be affected by damp- 
ness, and makes them somewhat heavier, 
which is an advantage to the two larger 
j)lanes. 
Mr. Carpenter also showed the bo^^s 
how to draw the " irons " out of the planes 
by "tapping " the " starter " gently with 
a hammer or mallet; he also described 
the uses of the different planes, stating 
that the jack plane was used for taking 
off the rough surface of lumber, or cutting 
down irregularities. He showed them 
that the iron should be ground a little 
rounding, to enable it to work well on 
rough stuff. The fore plane, or try- 
plane," as some workmen call it, he said, 
was for the purpose of making the surface 
stuff straight and square. It is Indispen- 
sible in making glue joints, or doing any 
work where long straight edges are re- 
quired. 
(To be continued.) 
Water-Proofing with Paraffine. 
SOME time ago, a method was devised 
for employing paraffine as a means of 
rendering leather water-proof, also the 
various textile and felted fabrics, and, 
subsequently. Improvements have been 
made on this process, which consisted 
chiefly in combining the paraffine with 
various proportions of drying oil, it having- 
been found that paraffine alone, especially 
when applied to fabrics, became to a con- 
siderable extent detached from the fibre 
of the cloth after a short time, owing to 
its great tendency to crystallize. The 
Fig. 10 
Fier. ii. 
even and fair after the jack plane had 
taken off the rough. I will show you," 
he said, " how to use this and the other 
planes properly, when we get fairly to 
work, and in the meantime I will just 
say that the smoothing plane is used for 
smoothing off joints of frame-work when 
put together; for fitting work, squaring 
up end-wood, and smoothing work in 
general. It should be kept very sharp, 
and set very fine, and if in good order will 
make shavings like ribbons of silk. The 
jointer is used for jointing all kinds of 
presence, however, of even a small quan- 
tity of drying oil causes the paraffine to 
adhere much more firmly to the texture 
of the cloth, sufficiently so, it is found, 
for all ordinary purposes, from the oil 
gradually becoming converted into a te- 
nacious resin by absorption of oxygen. 
In the application of this substance for 
water-proofing, it is first melted together 
with the requisite quantity of drying oil, 
and cast into blocks, and the composition 
can then be applied to fabrics by rubbing^ 
them over with a block of it either cold or 
