1873.] 
AMERICAN AGRICULTURIST. 
465 
IBOYiS & ®ICIEiL3 ? (ODIL"irMrJ«Sa 
Xlie Doctor^ Talks. 
ABOUT A PIXCE OP LIMESTONE. 
Now, my young chemists, having found your limestone, 
what shall the next step be? "Young chemists," you will 
say, "we never thonght of being chemists." — Do yon 
know what chemists do? I do not mean that kind who 
ecII pills and have blue bottles in their shop windows; 
but chemists that have made great discoveries, sueb as 
Faraday, Davy, and Liebig, who are now dead, and 
Johnson, Gibbs, Smith, and many others who are living 
and working. They spend their time in trying to find 
out all about things, just as you want to find out about 
the limestone. When a strange substance is brought to 
one of these great chemists he does just as you have 
done with the piece of limestone ; be looks at the color, 
tries how hard it is, tries if it has any taste— in short, 
first tries his senses upon it. Then if he wishes to know 
more about it he does just what I wish you to do with the 
limestone. He begins to ask it questions. "Ask it ques- 
tions y— the idea of asking a stone questions ! " Do not 
laugh, but wait until I explain. You put the vinegar 
question to the limestone last month, and the answer 
•was — bubbles. Now let us put another question : "What 
effect has heat upon limestone? 1 ' To get an answer to 
this you must break a piece up into small fragments and 
put some of them in a strong coal fire, where they will get 
not only red hot, but white hot. The bits should not be 
larger than a hazel-nut or a small walnut, and be placed 
where the fire is very hot. Do not be in a hurry for the 
answer, for you must wait for three or four hours, accord- 
ing to the kind of limestone, the size of the pieces, and 
the hotness of the fire. I have no doubt that those who 
burn wood instead of coal can make the experiment 
quite as well by placing their bits of limestone among 
the live coals on the hearth, but they may have to keep 
► it there longer When the limestone has been cooked 
for three or four hours you may take it out and place it 
on the sLove hearth to cool. What has been the effect 
of heating it? If the limestone had any shiny particles 
in it before heating you will not see any now, but the 
whole will look dead white. The pieces will be much 
lighter than before, and if you weighed them before and 
after heating you would find that they had lost a large 
share of their weight— nearly half; or to speak mere ac- 
curately, forty-four hundredths. That is, if a hundred 
pounds of limestone were thoroughly heated in a strong 
furnace there would be but fifty-six pounds of it left. 
The pieces are just as large as they were before heating, 
but very much lighter. The heat has driven off some- 
thing. "What is it?" We will look into that after a 
while; but for the present we will not trouble ourselves 
about what is gone but consider that which is left. 
When your bits of burned limestone are quite cool you 
may proceed to examine them. I can not advise you to 
try your senses upon the stone after it has been burned, 
but yon may try one of the abundant things — that is water. 
Let a few drops of water fall upon one of the pieces 
placed in a saucer— only a few drops. They sink iu at 
once. In a few moments more put on a few drops more. 
These will probably hiss, steam will arise, the lump will 
ewell and crack and finally fall apart, and you will have 
only a dry powder ; perhaps more drops of water may be 
added and the powder take it up and yet remain dry. 
Now you will note two things : The addition of water to 
this burned limestone produces heat, and though you add 
a considerable quantity of water the stone falls to pieces 
and remains dry. You perhaps hardly need to be told 
that the beat has converted your limestone into Ume, and 
that you have been doing ou a small scale what is done 
in lime-burning in large 
kilns, where many tons 
of limestone are sub- 
jected to strong heat 
and made into lime, a 
substance so useful in 
many ways. Yoa have 
seen masons preparing 
mortar ; they throw 
water upon the lime; 
a great heat is produced, but as they wish the lime 
as a sort of paste they use more water than is needed to 
make it fall to pieces as a dry powder. You can try the 
experiment with the lime you have burned yourselves or 
with a piece of mason's lime. By dropping the water 
upon it carefully you will find it to grow very hot, and 
although much water has been added the lime remains 
perfectly dry. This is a most wonderful thing, and I wish 
you to look at it closely. I do not know that I can ex- 
plain it better than by saying that lime and water have a 
very strong liking for one another, or attraction, and 
that the combination of the two is a solid, although one 
of this singular partnership, water, is a liquid. If you 
bad the means to weigh accurately, you would find that 
23 parts or pounds of lime would take up or unite with 
9 parts or pounds of water and yet remain dry. The 
water departs from its liquid state and becomes a part, of 
a solid. I could tell you of many other cases in which 
water becomes a part of a so'id. Alum, for instance, is 
perfectly hard, and is nearly half of its weight water, as 
you can see by putting a piece upon a shovel and holding 
it over the fire, when the water will be driven off aB 
steam. But we are talking about lime, and not alum. 
When lime is freshly burned ii is called guick-Yime, which 
means live or active lime. When you have put upon it 
all the water it will take up it is said to be slaked — that 
is, its thirst for water is slaked. The masons call it 
" slacked." When lime is exposed to air for a consider- 
able time it falls to pieces from taking up moisture from 
the air, and is called air-slaked lime. Slaked lime being 
pose should be rather firm, and the colors bright and 
strong. Bookbinders use paper of this kind, and so do 
printers. It is well to select colors that have a strong 
contrast. Almost any color will make a good contrast 
with white ; but when you come to green, purple, orange, 
and such colors, you must use some taste in selecting 
those that will look best together. Thus, yellow and 
green will look very dull, while red and green will be 
bright. So red and purple will not do as well together 
as yellow and purple. Much of the beauty of this woven 
paper-work depends upon its neatness; hence the strips 
should be cut with great care all of the same width. The 
weaving is a simple process, and only requires patience, 
and by passing the slips over and under so that the one 
or the other color shall be uppermost a great number of 
patterns may be made. In fig- 
ure 1 is shown a numberof sim- 
ple patterns which will serve 
for practice iu order to get an 
idea of the way in which it is 
done, and in figure 2 is a design 
for a mat completed. This de- 
sign in fig. 2 is only one of 
many that an ingenious person 
can make. A neatly-made little 
mat will be a very nice thing for 
a Christmas present, for most 
persons value a thing, no mat- 
ter bow simple it may be, if 
made by the bands of the giver, 
more highly than they would a 
more expensive gift bought 
with money. After all, it is 
the loving tbougbtfulness that 
goes with the presents that 
makes them prized by all sens- 
ible persons. 
PAPER MAT. 
a compound of lime and water the chemists call it hydrate 
oT lime. The Greek word for water, which we may write 
hwtor, comes in play in many of our English words re- 
ferring to matters in which water is concerned ; thus we 
have hydraulics, hydrant, etc., and combinations of other 
substances with water are called by the chemists hydrates, 
and our lime when combined with water is hydrate of 
lime. " But the heat given out ?" I was sure you would 
want to know about that — and that is the most difficult 
thing to explain. Let ns try. If you have a piece of 
solid water— ice— you have to heat it to make it liquid 
water. If you have liquid water that you wisli to make 
solid, or ice, you have to take away heat from it, or 
cool it. A certain amount of heat is necessary in order 
that water shall remain in a liquid state. Well, when we 
put the water and the lime together they like one another 
so much that they will unite and form a solid compound 
—the slakedlimc; and the heat having nothing to do any 
longer in keeping the water liquid just escapes, and the 
lime becomes very hoi. How great this heat is you see 
when the masons slake a large quantity of lime, and it is 
shown more strikingly still when a vessel loaded with 
Fig. 1. — PATTERN FOR PAPER MAT. 
lime pprin^- a leak. The action of the water npon the 
lime then produces heat enough to set the vessel on fire, 
and many disasters have been caused in this way. But I 
think that this lesson upon lime is long enough for once. 
Let us suppose you have slaked your lime In a saucer or 
other convenient dish; now add water gradually, and 
stir it until the whole forms a milky liquid; pour this 
into a bottle, a pint bottle or one smaller will do ; then 
fill it quite, up with water, cork it, and set it aside until 
the next talk. 
Paper Weaving;. 
We have seen very pretty mats woven with strips of 
paper of different colors. The paper chosen for this pur- ■ 
Aunt Sue's Puzzle- 
Uox, 
NUMERICAL ENIGMA. 
I am composed of ten letters. 
A carpenter stopping at an 5, 
10, 6 sharpened his 3, 2, 1 by 7, 
2, 3 light. After finishing his 
work he drank a little 7, 5, 10 
out of a 8, 5, 6 cup, and then 
put on his 4, 2, 8 to 7, 9 out. 
My whole was where he lived. 
Harrison Snyder, 
diamond puzzle. 
The center letters — horizontal and perpendicular— per- 
tain to the culture of flowers. 
1. The commencement of war. 
2. A fluid. 
3. Undaunted. 
4. Circuitous.' 
5. A model. 
6. Reliable. 
7. A subject of consideration with farmers. 
8. A delightful employment for ladies 
9. Not governing. 
10. Brighten life. 
11. The occupation of many a gentleman of leisure, 
12. A region. 
13. A girl's name. 
14. A conjunction. 
15. Part of an egg. 
RIDDLE.^ 
My home is the whole globe. I sometimes live in the 
air, sometimes in the clouds, sometimes in the trowels of 
the earth, and some- 
times on the surface. 
Wherever I go there are 
some who welcome me 
and some who dislike 
me. Children can not 
live without me, and 
yet I am of no use to 
them. Sometimes I 
betoken sorrow and • 
sometimes happiness. And now 1 ask you to find ray 
name although I am invisible. Chs. W. Shelmire. 
CHEMICAL PUZZLE. 
I am four-fifths of what you daily breathe, 
The other fifth within your Inngs I leave; 
Starvation in young plants I keep away; 
From fiercest fire I pass unharmed away. 
R. T. Isbester. 
ANAGRAMS. 
1. Let parson. 6. Eden, Master N. 
2. Leaving rest. 7. See plant burn. 
3. Slim cheap cod. 8. I a fit leaf. 
4. Able scion. 9- Fault in line. 
5. In fact in gem. 10. But not rice. 
Wm. L. E., Jr. 
