438 
AMERICAN AGRICULTURIST 
[October, 
TOYS & ©IMS’ TOMMMSc 
Tlae Ifcoctor’s 'ITjiIIas*. 
We have been for a while somewhat off of our regular 
track, and have talked about insects and other things, but 
now that the weather is getting cooler and the evenings 
longer, we feel more like reading those things that re¬ 
quire some thinking about, let us get back to our talk 
about Matter. Heretofore we have talked about solid 
substances, and I mentioned at the beginning, that we 
knew of matter in three states, solid, liquid, and gaseous. 
Do you ever think of the difference between a solid and 
a liquid? How would you define it ? Perhaps you would 
say that a solid stands by itself, while a liquid requires 
something to hold it.; and that would be a very good 
definition. But to go back to some of our earlier talks ; 
you recollect that it was stated that all Matter was sup¬ 
posed to be made up of minute parts or atoms. Not 
that any one has ever seen these, because they are too 
small to be visible by the most powerful microscope ; 
but all reasoning shows that these really do exist. You 
will still further recollect that it was said that these 
atoms were held together by a force called Attraction or 
the Attraction of Cohesion. We know that this forco is 
very great in steel, as we cannot break it or overcome 
the force of attraction, withoutgreat trouble. Buta lump 
of sugar is readily broken. The attraction between the 
particles of steel or atoms of steel is much stronger than 
between the atoms of sugar. In solids we find every de¬ 
gree of hardness, and hardness measures the force of 
this attraction ; steel is harder than lead, lead is harder 
than sugar, sugar is harder than soap. When the at¬ 
traction between the particles of a subtance is so weak 
that it cannot hold its shape, then we have a liquid, and 
we have any degree of liquidity between such half 
liquids as tar and such a perfect liquid as water. But 
all liquids take the form of some solid vessel which 
contains them. Left to themselves, they spread about 
and have no definite shape of their own. Heat is the di¬ 
rect opposite of the attractive force. If we wish to 
overcome the attraction between the particles of lead 
we put the metal in a ladle over the fire and it soon be¬ 
comes a liquid. Heat has destroyed the force of attrac¬ 
tion between the particles of lead. So with a liquid; if 
we abstract the beat, and allow the force of attraction to 
act, it soon becomes a solid, as with water. We have only 
to extract a certain amount of heat from water, and it 
at once becomes the solid ice, having all the properties 
ol other solids. But we shall say more of heat at another 
time, as it is one of the most interesting subjects of any 
that we have to deal with. 
But it is safe to say that the condition of Matter, 
whether solid or liquid, depends, as a general thing, 
upon heat, there being but few liquids that have not 
been reduced to the solid state by abstracting the heat, 
or what is the same thing, by exposing them to an in¬ 
tense amount of cold; and there are not many solids 
that, by the application of sufficient heat, have not been 
brought into the liquid state. What we wish now to 
take up is, the mechanical properties of liquids. As in 
solids, there is a wonderful difference in the density or 
weight, so there is an equal difference in liquids. The 
heaviest liquid, of which we have any knowledge, is 
quicksilver or mercury. This is fourteen times heavier 
than water. On the other hand we 
have liquids much lighter than wa¬ 
ter; you know that most oils will 
float upon the surface of water, be¬ 
cause they are lighter, and there are 
liquids still lighter than any oil. 
You will recollect that in comparing 
the weight something was said 
about Specific Gravity. The Specific 
Gravity of a solid is its weight as 
compared to an equal bulk of water. 
So with the specific gravity of liq¬ 
uids. Water is taken as the stan¬ 
dard of comparison, and when we 
say that the specific gravity of mer¬ 
cury is fourteen, we mean that a 
given bulk of it, for instance a 
tumblerful of it, would weigh four¬ 
teen times as much as the same 
tumbler full of water. Not only 
are the liquids heavier than water, 
compared in this way, but also those that are lighter than 
water, using the minus sign. The specific gravity of 
ether is stated as .713. Perhaps you would like to know 
how the specific gravity of liquids is taken. There are 
two ways. One is to have a bottle that holds up to a 
mark on the neck, just a thousand grains in weight of 
water. If this bottle be filled up to the mark with 
quicksilver instead of water, and weighed, the bottle 
being balanced of course, the weight will be found to 
be fourteen thousand grains. So if we fill it to the mark 
with ether and weigh it, the weight will be about .713 
grains instead of the thousand; so we say that the 
specific gravity is —713. This, however, is a slow method 
of taking the specific gravity. A little instrument called 
the Hydrometer is used for this purpose, that long word 
meaning water measurer. The common shape of the 
hydrometer is shown in figure 1. This you see is a glass 
bulb, to the upper part of which is attached a stem on 
which figures are marked. Below it is weighted with 
shot in order to make it float upright in the liquid. 
When this is placed in pure water, the point to which 
Fig. 2.— THE “ POCKETS.” 
the instrument sinks is marked upon the stem. If this 
be placed in a liquid that is heavier than water, it will 
not sink so deep, and if it be placed in a liquid lighter 
than water, it will sink deeper. By the use of this in¬ 
strument, we may easily learn the specific gravity of any 
liquid in which it may be placed. In practice there are 
two kinds, one for liquids lighter than water, and one for 
liquids heavier than water, as it would require too long 
a stem to have one instrument answer for both. These 
hydrometers are used in testing various spirits, acids, 
and such liquids the strength and value of which depend 
upon their specific gravity. 
For example, Sulphuric Acid, or as it is more generally 
called, Oil of Vitriol, is largely used in a great number 
of manufactures—indeed so important is it in the vari- 
ious arts, that a distinguished man once said that the 
rank of a nation as to its arts and manufactures could 
bo told by the amount of Oil of Vitriol it used in a year. 
When this is of proper strength, it is almost twice as 
heavy as water—its proper.specific gravity being 1,845. 
If the bottle before mentioned as holding 1,000 grains of 
water, was filled with Sulphuric Acid, it would weigh 
1,845 grains. The maker of the acid might add a fourth 
of its bulk of water, without the knowledge of the pur¬ 
chaser. But the purchaser can at a glance tell whether 
his acid is of the proper strength, by plunging the Hy¬ 
drometer into a portion of it. So the Hydrometer is not 
merely a scientific toy, but comes into use in business 
life .. .But we can not just now say more about liquids 
as there is 
AN INTERESTING WHAT IS IT? 
to be disposed of. My young friend, Edwin K., sends 
something which was found on the shore of Long Island 
Sound. How his “ some¬ 
thing” looks is shown of 
the real size, as to width, in 
figure 2, but was, when 
found, about eight inches 
long. It consisted of many 
oval pockets, each attached 
by one of its broad sides to a 
sort of cord that held the 
whole together. These pock¬ 
ets were of a material much 
like parchment, or dried 
bladder in appearance, and 
like those substances, ex¬ 
ceedingly tough. What may 
be called the front edge of 
these pockets, that is, the 
edge opposite that by which 
they are attached to the cord, 
Fig. 3. — THE PERI- is slightly wavy or “ ruffled,” 
winkle shell. and there is a small hole at 
this part. When one finds a thing that seems strange 
to him he should first 
PUT QUESTIONS TO IT, 
before putting questions to us. Had Edwin, by shaking, 
asked if there were anything inside of these pockets, 
the rattling sound would have said “yes,” just as plainly 
as we can. Then the next question would be—“What 
is inside of these ?” only you would have to ask it with 
the point of a sharp knife—a little cut, a small opening, 
and out drop several little things, which rattle down 
upon the paper you have placed to catch them. These 
things that were in the pockets, what are they—they do 
not look like grains of coarse sand, but to make the 
matter clear you take a magnifier and lo 1 the story is 
told— 
THE GRAINS ARE LITTLE SHELLS ! 
and you know at once that this string of pockets or bags 
is somehow concerned with the early growth of a creature 
that has a shell. Those of you, who live near the sea 
shore, must have often seen a shell like that in fig. 3.— 
only twice as long and wide, and even larger. This shell 
is shown empty, but it, of course, at some time con¬ 
tained an animal. On our shores this is called 
THE PERIWINKLE, OR WHELK, 
but is unlike the creatures known in England by those 
names. The material, sent by my young friend, is the 
spawn cases of this animal. I suppose that when this 
spawn is first laid by the animal, there are eggs in the 
pockets, but I never came across any in which the eggs 
had not been hatched, and the tiny Periwinkle had each 
a minute shell, like the large one in shape. Some per¬ 
sons eat the Periwinkle, placing them in water and boil¬ 
ing them, when the animal may be easily removed from 
its shell. Seeing others eat them, I once tasted a Peri¬ 
winkle—that taste has answered for half a century, and 
I don’t thinkl shall ever repeat it. The shells are used 
by boat-builders. You notice what a long spout, so to 
speak, it has ; the boat-builders use them to run tar into 
cracks when they are “ caulking ” the seams of their 
boats ; the body of the shell being filled with tar, it can 
be poured out through the long, narrow spout, in a very 
small stream. The scientific name of our Periwinkle is 
Pyrula ccinaliculata. Pyrula is from Pyrus, the Latin 
word for “Pear,” and canaliculata is from the Latin 
word for a “channel,” and means, having a small chan¬ 
nel. If the scientific names of animals and plants look 
hard and unmeaning to you at first, they will seem differ¬ 
ent when you learn from what they are derived. A look 
at the engraving shows that—“The pear-shaped shell 
that has a little channel,” describes it very clearly ; Py¬ 
rula canaliculata , is only a shorter way of saying it. 
Our I*iiz*Ie-!Box. 
CONCEALED FABRICS. 
1. Jennie is forever bringing Hamburg edging home 
with her. 
2. The plant was recommended to me by a farmer in 
Ohio. 
3. She had read the poems of Walter Scott, only. 
4. Tom said he had never read a line, never wanted to, 
and never meant to. 
5. That is a pretty old fossil, Kate. 
6. Is a tin trumpet a musical instrument ? 
7. We need not fear, they will not harm us, Lincoln. 
8. Is the composer German or French ? 
9. As soon as I spied the rascal I concealed the money. 
NUMERICAL ENIGMA. 
I am composed of 7 letters: 
My 7, ti, 5, 1, is a measure. 
My 3, 2, 1, is the whole of anything. 
My 7, 2, 3, 4, is unorganized earthly matter. 
My 7, 5, 6, 4, is a weapon. 
My 6, 2, 3, 4, is a metallic oxide. 
My whole may sometimes be seen in a drug-store, some¬ 
times on the dinner table, and sometimes in the garden. 
Perry McI. 
cross-word. 
My first is in hobble but not in limp. 
My next is in edging but not in gimp, 
My third is in hatchet, but not in ax, 
My fourth is in honey but not in wax, 
My fifth is in letter but not in bill. 
My sixth is in valley but not in hill, 
My seventh is in river but not in lake. 
My eighth is in fritter but not in cake, 
My ninth is in pleasures but not in joys. 
My tenth is in bustle but not in noise: 
Now take my advice and be happy and gay, 
No matter what any old croaker may say. 
DEFINITION PUZZLES. 
(Letters with which to form the word defined may be 
found scattered in each sentence.— Example. That by 
which anything is regulated. Word, rule.) 
1. The little wheel of a spur. 
2. Pertaining to life, very important. 
3. Practice, custom. 4. A sort of scuffle. 
5. Second growth of grass. 
6. Very poisonous, malignant. 
7. A place of worship. 8. A piece of mechanism. 
pi. 
Veah ourcage onehug ot viewer oury now tonccud, ot 
doncmen ti hewer ouy det.tec fulsat, ot maden ti ot het 
steb fo oury bcllity, ot kame dogo loversse orf ruetuf 
aceduing, dan ot peek metli. 
SQUARE WORD. 
1. A friend. 2. Fat. 3. An asteroid. 4. To impede. 
5. Cuts down. Little Folks. 
CHARADE. 
Hark 1 the morning bell is ringing 
From the steeple loud and clear, 
And the pious crowd is wending, 
Keverent souls, my first to hear. 
On my next the grass is growing. 
Maybe ’tis a city lot, 
Upon the globe in every land, 
I’m sure to find my space and plot. 
The hideous whole, how shall I name it! 
Cruel, bloody, fearful strife ; 
I dare not tell the countless numbers 
That through me have lost their life. 
Aunt Sue. 
word-making. 
(To one of the words in a list, add the letter at the 
end, and with it transpose the word into another.) 
1. List: make, house, slow, phial, them, many; letter,C. 
2. List: toe, hold, martyr, coward, lyre, he; letter, B. 
3. List: hungry, greed, boots, eye, mustard, cow; 
letter, L. 
4. List: dreamer, broom, servant, gold, zone; letter, E. 
