144 THE YOUNG 
Too Much Philosophy. 
SOME people are always ready with a 
theory for every phenomenon. In 
general they depend upon electricity " 
for a solution of any problem which pre- 
sents itself, but as this has of late been run 
into the ground, they resort to new spec- 
troscopic theories for the heat, or in severe 
winters to gulf-stream theories for the 
cold. A gentleman who had a great con- 
tempt for such theorists, and who ex- 
pected a visit from some of them, had in 
his garden one of the well-known carboys, 
■or globular bottles of dark glass, in which 
.sulphuric acid had been kept. Such bot- 
tles form a mirror in which the surround- 
ings are seen reflected on a very small 
scale, and might be looked upon by some 
as heat concentrators. The bottle was 
lying on the ground in the sunshine, and 
the professor made his guests observe that 
singularly the upper side, exposed to the 
sun, w^as not so hot as the lower side. At 
once a few of the learned friends said that 
-of course this must be so, because the dark 
glass was very transparent to the caloric 
rajs, which, therefore, did not heat it, but 
passed through and were absorbed under 
the bottle by the ground, which then 
lieated the under side of the bottle by con- 
duction. Others held that the form of the 
bottle was the cause ; the upi)er side being 
•convex, distributed the rays by reflection, 
while the under side being struck by the 
rays on its concave surface, concentrated 
them. A few other theories were pro- 
pounded, to none of which our professor 
agreed, when flnally his friends insisted 
that he should give an opinion as to the 
cause of the bottle's being hotter below 
than above. He said that he had turned 
it round, upside down, just when they en- 
tered the garden. 
»-o-« 
To Our Subscribers. 
THE confusion attendant on certain 
changes in our location and business, 
and the failure of certain parties to furnish 
articles and illustrations for which we had 
contracted, caused some delay during the 
summer months which proved very an- 
SCIENTIST. 
noying to our subscribers and to ourselves. 
There are two numbers more required to 
comi>lete the volume, and they will be is- 
sued without delay. Our arrangements 
now are such that the Young Scientist 
will be issued hereafter regularly and 
promptly. It is the only journal of the 
kind in the world, and we hope our young 
friends, and old ones too, will help us to 
make it better. This can only be done by 
aiding us to secure as many new subscrib- 
ers as possible. Let each boy and girl try 
and get us one new subscriber and the 
Young Scientist for 1880 will be a glorious 
success. And to encourage them to do 
this we would call attention to the liberal 
premiums which we offer. 
Who Wants a Knife? | 
EYEEY boy wants a good knife and no 
lady's work-basket is comi)lete with- 
out one. We have just purchased, at a great 
bargain, a few very excellent pocket knives 
of Sheffield manufacture. We have tried 
these knives and they are really good, 
notwithstanding the fact that we bought 
them so low that we can give one to each 
of our subscribers who will send us $1.00 
for his own subscription and that of some 
one not now a subscriber. 
These knives are of three different kinds. 
One is for boys ; it is a stout knife with two 
blades and buck horn handle ; one blade 
is large and strong for whittling ; the other 
is small. The second knife is lighter ; it 
has a large and a small blade, and the han- 
dle is of dark cocoa; it is an excellent 
knife for the vest pocket and for light 
work. The third knife is quite small ; it 
has two blades and a white handle with 
name plate on it. It is a lady's knife 
rather than a boy's. Those who secure one 
of these knives as a i^'emium can take 
their choice of any of tlie three. 
In addition to these knives we have the 
following, which are marvels of cheap- 
ness. No 1 is a sportsman's knife with 
stag handle. It has the usual blades with 
corkscrew, picker, gimlet, etc. Such a 
knife usually sells for $1.50, and we offer 
it to any one who will send us three sub- 
scriptions — two of which must be new 
names. 
