THE YOUNG SCIENTIST. 
141 
How to Sharpen a Pencil. 
Ed. Young Scientist— In youv prospectus you 
Bay that the Young Scientist is for teaching- us 
how to do things. Now, I would like very much 
to know the best way to sharpen a pencil. Papa 
has bought me two or three pencil sharpeners, 
but they are no good. When I use a knife I 
dirty my hands up, and the point of the pencil 
breaks, and it is Just awful. Please tell me how, 
and also what is the best sharpener, and I will 
thank you ever so much. Yours, 
A Little Girl. 
The experience of our young friend is the 
same as our own ; we have never found a pencil 
sharpener that we would accept as a gift. The 
best pencil sharpener is a g:ood sharp knife, 
and with it, it is easy to give a pencil either the j 
round, conical point used foi' writing, or the flat, ' 
chisel point used for drawing lines. j 
First of all, remove the wood with a series of j 
long clean cuts ; do not hack and nibble it, ! 
making it look as if the rats had eaten off the ' 
end. This requu'es a sharp knife, and, if your] 
hand is large enough, the best way to hold the | 
pencil is to lay the end on your thumb, and hold 
the knife in the four fingers. If your hands are j 
small you had better hold the pencil in the left 
hand, point outwards, and cut away from you ; 1 
in this way all danger of cutting yourself is I 
avoided. Do not attempt to cut the lead until 
you have cut away the wood so as to leave about , 
one-eighth of an inch exposed. As the lead is | 
quite brittle it must be supported, and most j 
persons lay it on th<3ir thumb, allowing the ! 
powdered black lead to fall all over their hands, | 
soiling them in a very disagreeable manner. In ' 
addition to the dust, however, the point of the j 
pencil is very apt to be broken, since the flesh is j 
soft and yielding. Therefore, the best plan is to j 
lay a piece of paper on a table or board, and on ; 
this lay the point of the pencil, flat. You can ! 
now shave off the black lead without any risk of | 
breaking it, and by constantly turning the pen- 
cil round, a beautiful conical point may easily 
be given to it without in the least degree soiling 
the hands or anything else, except the waste ' 
paper, which may be thrown away. j 
To carry out these directions, however, it is \ 
necessary to have a sharp knife, and one of which ' 
the blade is not too soft. Draughtsmen and en- 
gravers frequently use a file or a piece of fine | 
sand-paper for sharpening pencils, and they an- ' 
swer admirably. But after all we prefer a good 
sharp knife. i 
BOOK NOTICES. 
Trichinae (Pork Worms, or Flesh Worms): 
How to Detect Them and How to Avoid Theui. 
Being a Popuhir Account of their Habits, Modes 
of Propagation, and Means of Dissemination. 
Intended for the Use of Parmers, Butchers, 
Pork Dealers, and Consumers of Pork. By 
John Ph in, Editor of the American Journal of 
Microscopy. Bochester: The Bauscii & Lomb 
Optical Company. 
This little pamphlet has not been written from 
an alarmist standpoint, although it points out 
clearly and forcibly the danger to an important 
article of commerce if steps be not taken to stamp 
out what a German author calls "man's most 
dangerous enemy." So far as human beings are 
concerned, it has been clearly shown that we 
have, in the simple process of thorough cooking, 
a perfectly efficient means of killing trichiiiEe 
and all other parasites. But in order to be effec- 
tual, the cooking must be thoi»oagh; no mere 
surface scorching on the one hand, or brief dip- 
ping in boiling water on the other. It has long 
been known that a lump of flesh, placed in boil- 
ing Avater, may be very thoroughly cooked on the 
outside, while the interior has not reached a tem- 
perature high enough to destroy any parisite that 
may be present. And if this process of cooking 
be applied to all animal food given to pigs, dogs 
and cats, and if it be made a serious offence to 
manure with animal offal, land on which are to be 
grown grass or vegetables that are eaten in a raw 
state, the trichinae would soon be " stamped out." 
This pamphlet, which' may be obtained free 
from the Bausch & Lomb Optical Company, of 
Rochester, N. Y,, gives very clear engravings, 
showing the trichinee at its different stages, and 
it also describes a very simple and efficient in- 
strument for detecting the pest. 
Practical Hints on the Selection and Use of 
the Microscope: Intended for Beginners. 
By John Phin. Editor of the American Journal 
of Microscopy. Fourth Edition. Thoroughly 
Bevised and Oreatly Enlarged. Illustrated with 
six plates and 80 figures in the text. New York: 
Industrial Publication Co. 
It is but a short time since we noticed the issue 
of the third edition of this work, and yet that 
edition is already exhausted and a fourth pub- 
lished. Some additions have been made to this 
edition, and the work is now so large that the 
publishers no longer find themselves able to sell 
it for seventy-five cents. The price has therefore 
been raised to one dollar. While it never can 
prove a substitute for the larger works of Beale. 
Carpenter, or Prey, it has shown itself to be a 
most useful volume for the beginner and the 
amateur. 
The Rain Drop: A Monthly Miscellany of En- 
tertaining Reading for Young People. Pitts- 
burgh, Pa.: James Logan. 
We have frequently noticed this interesting 
journal during the course of its publication, and 
now that it has closed its career, we call attention 
to it as one of the very best Christmas gift books 
