1883.] 
AMerioau agriculturist. 
3*79 
from the front and center of the body to the side 
•with each arm, bringing each to its original posi¬ 
tion in one exercise, or to “One,” in continuous 
swimming. 
Motions of Legs . — One (on land.) Keep the feet 
together, and let the weight of the body spread 
the knees as far as convenient. (In water.) Keep 
the feet together, and draw up the legs, with 
the knees widely extended. Two. Spread the 
feet so that, from the knees down, the legs will be 
straight, and, of course, spread to full extent. 
(On land.) Jump up and spread the legs. Three. 
Bring the legs to the original position. No bet¬ 
ter instructor for this movement in the water 
can be found than the frog. 
Practice on land first with hands, then with feet, 
and finally with both together, dropping the num¬ 
bers (One, Two, Three,) when thoroughly familiar 
with the motions. By fitting a surcingle, webbing, 
or base-ball belt to the chest of the learner, and at¬ 
taching this to a rope or strap suspended from a 
pole, in the hands of a trustworthy person, two or 
three exercises in the water will give the learner 
confidence in himself, and he can swim. (Perhaps 
the Doctor will explain, when be sees fit, the forces 
employed, and the results obtained.) 
“ Treading,” or “ tramping ” water is very easily 
acquired, and is sometimes very welcome—per¬ 
haps the means of saving life. Stand in water per¬ 
pendicularly, swimming only with the hands, to 
keep yourself up ; draw up the feet about six or 
eight inches, and straighten them out; continue 
the motion; dispense with the support of one 
hand, and when you have sufficient confidence, 
cease to support yourself with either. 
It is not difficult, after learning to swim with 
hands and feet, to swim on the back with legs only, 
aud rest the lungs and arms as much as possible. 
B. 
How One Insect Made Trouble. 
Something happened, not long ago, in one of the 
large public schools of New York City, which shows 
how important it is that children should be taught 
about common things. Among the ignorant, the 
common dragon-flies are looked upon with dread, 
not only by children but by older persons. It is a 
common belief that if one is stung by a dragon-fly, 
deafness will follow, and children are told that 
these “ Devil’s darning-needles,” as they are called, 
will sew up the mouths of the naughty ones. 
These insects might cause much pain if they only 
had stings, but they can no more sting than they 
can sew, and children should not be taught such 
nonsense about the beautiful and harmless dragon¬ 
flies. In one of the city schools there were, in an 
upper room, over nine hundred children. A 
dragon-fly flew in at a window and began to sail 
about over the heads of the youngsters. Many of 
the children took fright and ran screaming down 
the stairway into the street, some of them crying 
“ fire! ” Boys were in the room below, who, 
hearing the cry, started for the doors, but were 
soon checked by the teachers. The cry of fire 
reached the street, a large crowd at once gathered, 
the fire engines came, and there was a tremendous 
excitement — all on account of one little “dragon¬ 
fly.” Fortunately, the children were quieted be¬ 
fore they could crowd and crush one another on 
the stairs. Had a real panic taken place no doubt 
many lives would have been lost. Had children 
been taught that the dragon-flies can neither sting 
nor injure them in any other manner, they would 
not have been frightened by the appearance of one 
in the school-room. The insects do good rather 
than harm, as they devour great numbers of mos¬ 
quitoes, and their wings are so beautiful, while 
their flight is so rapid and noiseless, that they 
are objects to be admired rather than dreaded. 
The Doctor's Talks. 
“ How is cork made ? ” writes a young friend in 
Maryland, who, like some older persons, thinks 
that cork is a manufactured product. You have 
no doubt noticed that the bark in different trees 
and shrubs is very unlike 
in appearance. In some, 
the bark is brittle, while 
in others it is exceedingly 
tough ; so strong, indeed, 
as to be used instead of 
rope and cord. The bark 
of a tree or shrub is not 
alike all through, but is 
made up of three different 
layers, and these layers 
are so unlike in their na¬ 
ture, that the bark differs 
in character as one or the 
other of these is more 
abundant. The bark of a 
young twig has (beginning 
next the wood) 1st, the “In¬ 
ner Bark ” {Liber), which 
is usually very tough, as in 
the Basswood, the inner 
bark of which is so useful. Outside of this, in the 
young twig, is a “ Green Layer.” This is covered 
with the “Corky Layer,” and outside of all is a 
very thin skin, which covers the whole. We will 
say no more at this time about the other parts of 
the bark of a trunk or branch. It is the corky layer 
that most interests us. On a young shoot, this 
only appears late in the season, and it is this which 
gives the peculiar color to the bark, by which you 
can often tell a tree from the color of its young 
branches. In most of our trees, this corky layer 
does not increase much in thickness, but as the 
tree gets old, this, with the other outer portions of 
the bark, decays and falls away. In the Whahoo, 
or Winged Elm, and in the Sweet Gum, or Bil- 
sted ( Liquidambar ), both trees that are found in 
Maryland and various other States, especially south¬ 
ward, the corky layer continues to grow for sev¬ 
eral years. The small branches of both these trees 
have projecting wings or ridges, which consist of 
an unusual growth of the corky layer. In these 
trees this layer grows very irregularly, but in 
AN OAK OF SOUTHERN EUROPE 
it continues to increase, and form a thick, regular 
sheet; this is what we know as Cork. The Cork 
Oak is a fine large tree, with small evergreen 
leaves, and produces acorns which are eatable, 
much resembling chestnuts in taste. In this oak, 
the corky layer, so small in most other trees, forms 
a coat, one to nearly two inches thick, which, if left 
to itself, would fall away from the tree in about 
ten years. For use, the cork is separated about 
two years before it would naturally fall away. 
Lengthwise cuts are made through this portion of 
the bark, and cross cuts above and below them. 
By means of short levers, the cork is pried off, 
care being taken not to injure the inner bark. The 
engraving, showing a company of cork gatherers, 
explains the manner in which they work. The 
“ Cork Bark,” also called “ Cork Wood,” is stack¬ 
ed up in pits, loaded with heavy stones, and water 
is let in. After the pieces have soaked for a time, 
they will keep the flat shape given them by the 
weights. In some places the surfaces of the cork 
are charred, but this is not done to the finer kinds. 
THE REMOVAL OP THE CORK 
does not injure the tree, and it is repeated every 
six or eight years. Cork differs greatly in quality, 
the finer kinds, known as “ velvet-cork,” bringing 
a much higher price than the common sort. The 
great use of cork is to make stoppers to bottles 
and other vessels, and for this purpose no substi¬ 
tute has been found or artificially made. It is 
A DRAGON PLY. 
GATHERING CORK from CORK OAK trees (Quercus suber).—Engraved for the American Agriculturist. 
