THE YOUNa SCIENTIST. 
113 
at A, is not bound together, but is left 
free, so that it can be expanded to the size 
of any ordinary lamp chimney. To the 
bottom, and half way up the sides of the 
wire frame, che edges of the cardboard 
are sewed, after which the cardboard is 
bound with green ribbon. The lamp- 
light effect of such a shade is very pleas- 
ing and soft. 
How to Join a Lead Pipe. 
BY AN AMATEUR. 
AN amateur who can do one thing 
thoroughly well, and who under- 
stands the reasons for each step in the 
process, will easily extend his knowledge 
and skill to analogous cases. Now, there 
is scarcely a more useful handicraft in 
the home, especially in frosty winters, 
than plumbing; and the amateur who 
possesses even moderate knowledge of 
the craft will save his household a vast 
amount of inconvenience, and himself no 
small expense. The object of this paper 
is to describe the method of making a 
joint in a lead pipe running down the 
a,ngle of a room, or in any similar position 
in which there is no side strain. Such a 
pil^e is often split open by the frost, and 
it becomes necessary to cut away the 
damaged i^iece, and to replace it by a new 
length, involving the making of two joints, 
one at each end of the new piece. 
In making such a joint, there are three 
distinct stages in the process :— 
1. Shaping the ends of the pipe. 
2. Putting in the solder. 
3. Making the joint. 
AVhere the amateur has most likely gone 
wrong has been in not attending to the 
distinction between 2 and 3, or perhaps in. 
ignoring 3 altogether. The consequence 
is his joints leak, or even come apart 
without effort, 
1. Shaping the Pipe.— The two ends to 
be joined should be cut off square with a 
small-toothed hand-saw. Then the open 
end of the lower pipe is to be spread out 
funnel- wise, by driving into it a cone of 
box wood made for the purpose. It is 
something like an elongated peg-top. and 
maybe had for a few cents at a tool-shop. 
A few blows on the top of it, when placed 
in the open pipe, will soon produce the 
funnel shape. The end of the upper pipe 
must now be rasped all round, so as to fit 
easily into the funnel opening of the lower 
pipe. This rasping will reduce the thick- 
ness of the pipe at its opening to perhaps 
one-sixteenth of an inch, but care must 
be taken not in any way to crush up the 
pipe, so as to choke the waterway through 
it, or stoppages may occur when it is in 
use. 
The end of the upi^er pipe now drops 
easily into the funnel of the lower one, so 
as to leave a narrow channel all round the 
top of the funnel outside the upper pipe. 
2. Putting in the Solder. — The tools and 
appliances for plumbing and soldering 
are very few and simple. The chief agent 
is heat, and the chief operation applying 
that heat under the proper conditions for 
it to do its work in uniting the pieces of 
metal. Naw, for the solder to take to the 
lead, it is essential that the parts of the 
lead pipe to be united should be perfectly 
bright and clean. If they are at all 
oxidized or dulled, as lead always becomes 
after exposure to the air, the solder will 
not take. With a pocket-knife scrape the 
inside of the funnel-shaped pipe-end per- 
fectly bright ; if the lead pipe is old, there 
will be seams of corrosion in it that must 
be carefully cut or scraped out, otherwise 
the joint may leak. Take care not to droi> 
the chips of lead down the pipe, or they 
may cause trouble elsewhere. Then tiie 
outside of the rasped end must also be 
scraped perfectly bright, unless the rasp- 
ing has done this sufficiently. The proper 
tool for this scraping is a "shave-hook," 
a triangular piece of steel at the end of a 
short handle, but a i)ocket-knife will 
answer every purpose. The bright sur- 
faces soon get dull on exposure to the air, 
but as the joint is going to be made at 
once, there is no need to protect the 
scraped lead in waiting. 
When the metal is highly heated, the 
action of the oxygen of the air upon it is 
much more rapid, and as, in making the 
joint, the solder itself is melted, and the 
lead surfaces nearly so, it becomes neces- 
sary to protect the bright surfaces with 
wliat is called a "flux," to keep the air 
off tliem when they are raised to the high 
