Scientific American Supplement, No. 497, July 11, 1885
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Various >> Scientific American Supplement, No. 497, July 11, 1885
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I come now to a third point. That which has just been said applies
chiefly to things whose price is fixed by beauty. But handicraft gives
us many works not pleasing to the eye, yet of the highest skill--a
Jacquard loom, a Corliss engine, a Hoe printing press, a Winchester
rifle, an Edison dynamo, a Bell telephone. Ruskin may scout the work of
machinery, and up to a certain point may take us with him. Let us
allow that works of art marked by the artist's own touch--the gates of
Paradise by Ghiberti, a shield by Cellini, a statue by Michael Angelo,
are better than all reproductions and imitations, better than plaster
casts by Eichler, electrotypes by Barbedienne, or chromos by Prang. But
even Ruskin cannot suppress the fact that machinery brings to every
thrifty cottage in New England comforts and adornments which, in the
days of Queen Bess, were not known outside of the palace. Be mindful,
then, that handicraft makes machines which are wonders of productive
force--weaving tissues such as Penelope never saw, of woolen, cotton,
linen, and silk, to carpet our floors, cover our tables, cushion our
chairs, and clothe our bodies; machines of which Vulcan never dreamed,
to point a needle, bore a rifle, cut a watch wheel, or rule a series
of lines, measuring forty thousand to an inch, with sureness which the
unaided hand can never equal. Machinery is a triumph of handicraft as
truly as sculpture and architecture. The fingers which can plan and
build a steamship or a suspension bridge, which can make the Quinebaug
and the Blackstone turn spindles by the hundred thousand, which can turn
a rag heap into spotless paper, and make myriads of useful and artful
articles from rough metal, are fingers which this age alone has evolved.
The craft which makes useful things cheap can make cheap things
beautiful. The Japanese will teach us how to form and finish, if we do
not first teach them how to slight and sham.
A fourth point is this. If hand-craft is of such worth, boys and girls
must be trained in it. This, I am well aware is no new thought. Forty
years ago schools of applied science were added to Harvard and Yale
colleges; twenty years ago Congress gave enough land-scrip to aid in
founding at least one such school in every state; men of wealth, like
many whom you have known and whom you honor, have given large sums for
like ends. Now the people at large are waking up. They see their needs;
they have the means to supply what they want. Is there the will? Know
they the way? Far and near the cry is heard for a different training
from that now given in the public schools. Many are trying to find it.
Almost every large town has its experiment--and many smaller places have
theirs. Nobody seems to know just what is best. Even the words which
express the want are vague. Bright and thoughtful people differ as to
what might, can, and should be done. A society has been formed in New
York to bring together the needed data. The Slater trustees, charged
with the care of a large fund for the training of freedmen, have said
that manual training must be given in all the schools they aid. The
town of Toledo in Ohio opened, some time since, a school of practical
training for boys, which worked so well that another has lately been
opened for girls. St. Louis is doing famously. Philadelphia has several
experiments in progress. Baltimore has made a start. In New York there
are many noteworthy movements--half a dozen at least full of life and
hope. Boston was never behindhand in knowledge, and in the new education
is very alert, the efforts of a single lady deserving praise of high
degree. These are but signs of the times.
Some things may be set down as fixed; for example, most of those who
have thought on this theme will agree on the points I am about to name,
though they may or may not like the names which I venture to propose:
1. Kindergarten work should be taught in the nurseries and infant
schools of rich and poor.
2. Drawing should be taught in schools of every grade, till the hand
uses the pencil as readily as the pen.
3. Every girl at school if not at home should learn to sew.
4. Every boy should learn the use of tools, the gardener's or the
carpenter's, or both.
5. Well planned exercises, fitted to strengthen the various bodily
organs, arms, fingers, wrists, lungs, etc., are good. Driving, swimming,
rowing, and other manly sports should be favored.
What precedes is at the basis of good work.
In addition:
6. With good teachers, quite young children may learn the minor
decorative arts, carving, leather stamping, brass beating and the like,
as is shown in the Leland classes of Philadelphia.
7. In towns, boys who begin to earn a living when they enter their teens
may be taught in evening schools to practice the craft of carpentry,
bricklaying, plastering, plumbing, gas fitting, etc., as is shown
successfully in the Auchmuty schools of New York. Trade schools they are
called; schools of practice for workmen would be a better name.
8. Boys who can carry their studies through the later teens may learn,
while at the high school or technical school or college, to work in wood
and metals with precision, as I have lately seen in the College of the
City of New York, at Cornell University, and elsewhere-colleges or high
schools with work-shops and practice classes. If they can take the
time to fit themselves to be foremen and leaders in machine shops and
factories, they may be trained in theoretical and practical mechanics,
as in the Worcester Industrial Institute and in a score of other places;
but the youth must have talent as well as time to win the race in these
hard paths. These are schools for foremen, or, if we may use a foreign
word like Kindergarten, they are Meisterschaft schools.
9. Youths who wish to enter the highest departments of engineering must
follow advanced courses of mathematics and physics, and must learn
to apply this knowledge. The better colleges and universities afford
abundant opportunities for such training, but their scientific
laboratories are fitted only for those who love long study as well as
hard. These are schools for engineers.
10. Girls are most likely to excel in the lighter arts--to design (for
furniture or fabrics), to embroider, to carve, to engrave, to etch, to
model, to paint. Here also success depends largely upon that which was
inborn, though girls of moderate talent in art, by patience, may become
skilled in many kinds of art work. Schools for this instruction are
schools of art (elementary, decorative, professional, etc.).
If there be those in this hall who think that hand-craft is adverse to
rede-craft, let me ask them to study the lives of men of mark. Isaac
Newton began his life as a farm-boy who carried truck to a market town;
Spinoza, the philosopher of Amsterdam, ground lenses for his livelihood;
Watt, the inventor of the steam engine, was mechanic to the University
of Glasgow; Porson, the great professor of Greek, was trained as a
weaver; George Washington was a land surveyor; Benjamin Franklin a
printer.
Before I close let me draw a lesson from the history of our land. Some
of you doubtless bear in mind that before the late war men used to say,
"Cotton is king;" and why so? Because the trades which hung on this crop
were so many and so strong that they ruled all others. The rise or fall
of a penny in the price of cotton at Liverpool affected planters in
the South, spinners in the North, seamen on the ocean, bankers
and money-changers everywhere. Now wheat and petroleum share the
sovereignty; but then cotton was king. Who enthroned this harmless
plant? Two masters of hand-craft, one of whom was born a few miles east
of this place in Westborough; the other was a native of England who
spent most of his days a few miles south of this city. Within five
years--not quite a century ago--these two men were putting in forms
which could be seen, ideas which brought our countrymen large measures
of both weal and woe. In 1790, Samuel Slater, once an apprentice to
Strutt and Arkwright, built the mill at Pawtucket which taught Americans
the art of cotton-spinning; and before 1795, Eli Whitney had invented
the gin which easily cleansed the cotton boll of its seeds, and so made
marketable the great crop we have spoken of. Many men have made more
noise in the world than Slater and Whitney; few if any can be named
whose peaceable hand-craft has done so much to give this country its
front place in the markets of the globe.
Let me come nearer home, and as I take my seat let me name a son of
this very town who loved hand-craft and rede-craft, and worthily aided
both--Isaiah Thomas, the patriot printer, editor, and publisher,
historian of the printer's craft in this land, and founder of the far
famed antiquarian library, eldest in that group of institutions which
gave to Worcester its rank in the world of letters, as its many products
give it standing in the world of industry and art.
Mindful of three such worthies, it is not strange that Salisbury,
Washburn, Boylston, and many more have built up this high school of
handicraft; it will be no wonder if others like minded build on the
foundations which have been so fitly laid.
* * * * *
MAKING SEA WATER POTABLE.
[Footnote: Read lately before the Manchester Literary and Philosophical
Society]
By THOMAS KAY, President of the Stockport Natural History Society.
The author called attention to the absence of research in this
direction, and how man, endowed to overcome every physical disability
which encompassed him on land, was powerless to live on the wide ocean,
although it is teeming with life.
The water for experiment was taken from the English Channel, about
fifty miles southwest of the Eddystone Lighthouse, and it was found
to correspond closely with the analysis of the Atlantic published by
Roscoe, viz.: Total solids 35.976, of which the total chlorides, are
32.730, representing 19.868 of chlorine.
The waters of the Irish Sea and the English Channel nearer to the German
Ocean, from their neighborhood to great rivers, are weaker than the
above.
Schweitzer's analysis of the waters of the English Channel, near
Brighton, was taken as representing the composition of the sea, and is
here given:
Sodium chloride 27.059
Potassium " 0.766
Magnesium " 3.666
" bromide 0.029
" sulphate 2.296
Calcium " 1.406
" carbonate 0.033
Iodine and ammoniacal salts traces
Water 964.795
________
1000.000
The chlorides in the--
Irish Sea are about 30 per mille.
English Channel are about 31 "
Beyond the Eddystone are 32 "
As the requirement for a potable sea water does not arise except in
mid-ocean, the proportion of 32 per mille must be taken as the basis of
calculation.
This represents as near 20 per mille of chlorine as possible.
From the analysis shown it will be perceived that the chlorides of
sodium and magnesium are in great preponderance.
It is to the former of these that the baneful effects of sea water when
drunk are to be ascribed, for chloride of sodium or common salt produces
thirst probably by its styptic action on the salivary glands, and scurvy
by its deleterious action on the blood when taken in excess.
Sodium chloride being the principal noxious element in sea water, and
soda in combination with a vegetable or organic acid, such as citric
acid, tartaric acid, or malic acid, being innocuous, the conclusion is
that the element of evil to be avoided is _chlorine_.
After describing various experiments, and calling attention to the power
of earthy matters in abstracting salts from solutions by which he hoped
the process would be perfected, an imperial pint of water from beyond
the Eddystone was shown mixed with 960 grains of citrate of silver and 4
grains of the free citric acid.
Each part of the chlorides requires three parts by weight of the silver
citrate to throw down the chlorine, thus:
3NaCl + Ag_{3}C_{6}H_{5}O_{7} = Na3.C_{6}H_{5}O_{7}+3AgCl.
The silver chloride formed a dense insoluble precipitate, and the
supernatant fluid was decanted and filtered through a rubber tube and
handed round as a beverage.
It contained in each fluid ounce by calculation about:
18 grains of citrate of soda.
1-1/2 " " magnesia.
1/2 " " potash.
1 " sulphate of magnesia.
1/2 " " lime.
1/5 " citric acid.
with less than half a grain of undecomposed chlorides.
To analyze this liquid therapeutically, it may be broadly stated that
salts of potash are _diuretic_, salts of magnesia _aperient_, and salts
of soda _neutral_, except in excessive doses, or in combination with
acids of varying medicinal action; thus, soda in nitric acid, nitrate
of soda, is a _diuretic_, following the law of nitrates as nitrate of
potash, a most powerful diuretic, nitrous ether, etc.; while soda in
combination with sulphuric acid as sulphate of soda is _aperient_,
following the law of sulphates, which increase aperient action, as in
sulphate of magnesia, etc.
Thus it would seem that soda holds the scales evenly between potash and
magnesia in this medical sense, and that it is weighed, so to speak, on
either side by the kind of mineral acid with which it may be combined.
With non-poisonous vegetable acids, and these slightly in excess, there
is not such an effect produced.
Sodium is an important constituent of the human body, and citric acid,
from its carbon, almost a food. Although no one would advocate saline
drinks in excess, yet, under especial circumstances, the solution of it
in the form of citrate can hardly be hurtful when used to moisten the
throat and tongue, for it will never be used under circumstances where
it can be taken in large quantities.
In the converted sea water the bulk of the solids is composed of inert
citrate of soda. There is a little citrate of potash, which is a feeble
diuretic; a little citrate and sulphate of magnesia, a slight aperient,
corrected, however, by the constipatory half grain of sulphate of lime;
so that the whole practically is inoperative.
The combination of these salts in nature's proportions would seem to
indicate that they must be the best for administration in those ailments
to which their use would be beneficial.
Citrate of silver is an almost insoluble salt, and requires to be
kept from the light, air, and organic matter, it being very easily
decomposed.
A stoppered bottle covered with India-rubber was exhibited as indicating
a suitable preserver of the salt, as it affords protection against
light, air, and breakage. As one ounce of silver citrate will convert
half a pint of sea water into a drinkable fluid, and a man can keep
alive upon it a day, then seven ounces of it will keep him a week, and
so on, it may not unreasonably be hoped, in proportion.
It is proposed to pack the silver citrate in hermetically sealed rubber
covered bottles or tubes, to be inserted under the canisters or thwarts
of the life-boats in ocean-going vessels, and this can be done at a
simple interest on the first outlay, without any loss by depreciation,
as it will always be worth its cost, and be invaluable in case of need.
* * * * *
THE ACIDS OF WOOL OIL.
All wools contain a certain amount of animal oil or grease, which
permeates every portion of the fleece. The proportion of oil varies with
the breed of sheep. A difference in climate and soil materially affects
the yield of oil. This is shown by analyses made of different kinds of
wool, both foreign and domestic. Spanish wool was found to have but
eight per cent. grease; Australian wool fifteen per cent.; while in some
fleeces of Pennsylvania wool as high as forty per cent. was obtained. To
extract the oil from the wool, a fleece was put in a tall cylinder and
naphtha poured on it. The naphtha on being allowed to drain through
slowly dissolved out the grease. This naphtha solution was distilled;
the naphtha passing off while grease remained--a dark oil having high
specific gravity and remaining nearly solid at the ordinary temperature.
I am indebted to Mrs. Richards for this method of extracting the oil.
The process is quick and inexpensive, and is applicable to the treatment
of large quantities of wool.
The object of these experiments was to find the readiest method of
separating wool oil into its bases and acids, and further to identify
the various fatty acids. A solution of the oil in naphtha was cooled to
15 deg. C. This caused a separation of the oil into two portions: a white
solid fat and a fluid dark oil. The first on examination proved to be a
mixture of palmitic and stearic acids existing uncombined in the wool
oil. The original wool oil was saponified by boiling with alcoholic
potash.
The soap formed was separated into two portions by shaking with ether
and water. On standing, the solution separated into two layers, the
upper or murial solution containing the bases, the lower or aqueous
solution containing the acids. This method of separation is very slow.
In one case it worked very well, but as a rule appeared to be almost
impracticable. Benzol and naphtha were tried, instead of ether, but the
results were less satisfactory. On suggestion of Prof. Ordway, potassium
chloride was added to the soap solution partially separated by ether and
water. This caused an immediate and complete separation. By the use of
potassium chloride it was found possible to effect a separation with
benzol and water, also with naphtha and water.
Another means of separation was tried by precipitating the calcium
salts, from a solution of the potash soap. From the portion of the
calcium salts insoluble in alcohol, a fatty acid was obtained with a
melting point and composition almost identical with the melting point
and composition of palmitic acid. The aqueous portion of the separation
effected by water and ether was examined for the fatty acid. The lead
salts of the fatty acids were digested with ether, which dissolved out
the lead oleate. From this oleic acid was obtained. This was further
purified by forming the Boreum salt of oleic acid. The lead salts not
soluble in ether were decomposed by acid. The fatty acids set free were
saponified by carbonate of potassium. A fractional precipitation was
effected by adding lead acetate in successive portions; each portion
sufficient to precipitate one-fourth of all the acids present.
The acid obtained from the first fractionation had the melting point at
75 deg.-76 deg., indicating an acid either in carbon then stearic or palmitic
acids.
The acids obtained from the third fractionation had a melting point of
53 deg.-54 deg. C. This acid in composition and general properties was very
similar to that obtained by freezing the naphtha solution of the oil,
and is probably a mixture of stearic and palmitic acids. These acids,
being in combination with the bases of the oil, would be set free only
on saponifying the oil and subsequently decomposing with acid.
In conclusion, I should say that but a small proportion of the fatty
acids exist in the wool oil uncombined; that the proportion of oleic
acid is small, and can only be obtained in an oxidized condition; that
the main portion of the fatty acids is composed of stearic and palmitic
acids in nearly equal proportions; that the existence of a fatty acid,
containing a higher per cent. of carbon than those mentioned, is not
fully established.--_N.W. Shedd, M.I.T._
* * * * *
A NEW ABSORBENT FOR OXYGEN.
OTTO, BARON V.D. PFORDTEN.--The author makes use of a solution of
chromous chloride, which he prepares as follows:
He first heats chromic acid with concentrated hydrochloric acid, so
as to obtain a strong green solution of chromic chloride free from
chlorine. This is then reduced with zinc and hydrochloric acid. The blue
chromous chloride solution thus obtained is poured into a saturated
solution of sodium acetate in an atmosphere of carbonic acid. A
red precipitate of chromous acetate is formed, which is washed by
decantation in water containing carbonic acid. This salt is relatively
stable, and can be preserved for an indefinite time in a moist condition
in stoppered bottles filled with carbonic acid.
In this process the following precautions are to be observed:
Spongy flocks always separate from the zinc used in the reduction, which
float about in the acid liquid for a long time and give off minute gas
bubbles. If poured into the solution of sodium acetate, they would
contaminate the precipitate; and when dissolved in hydrochloric acid,
would occasion a slight escape of hydrogen. The solution of chromous
chloride must therefore be freed from the zinc by filtration in the
absence of air. For this purpose the reduction is carried on in a flask
fitted up like a washing bottle. The long tube is bent down outside the
flask, and is here provided with a small bulb tube containing glass wool
or asbestos. The hydrogen gas liberated during reduction is at first let
escape through this tube; afterward its outer end is closed, and it is
pressed down into the liquid. The hydrogen must now pass through the
shorter tube (the mouthpiece of the washing bottle), which has an India
rubber valve. When the reduction is complete, the blue liquid is driven
up in the long tube by introducing carbonic acid through the short tube,
so that it filters through the asbestos into the solution of sodium
acetate into which the reopened end of the long tube dips. When washing
out the red precipitate, at first a little acetic acid is added to
dissolve any basic zinc carbonate which has been deposited. In this
manner a chromous acetate is obtained perfectly free from zinc.
For the absorption of oxygen the compound just described is decomposed
with hydrochloric acid in the following simple washing apparatus: Upon
a shelf there are fixed side by side two ordinary preparation glasses,
closed with caoutchouc stoppers, each having three perforations. Each
two apertures receive the glass tubes used in gas washing bottles, while
the third holds a dropping funnel. It is filled with dilute hydrochloric
acid, and after the expulsion of the air by a current of gas, plentiful
quantities of chromous acetate are passed into the bottles. When the
current of gas has been passed in for some time, the hydrochloric acid
is let enter, which dissolves the chromous acetate, and thus, in the
absence of air, produces a solution of blue chromous chloride. It is
advisable to use an excess of chromous acetate or an insufficient
quantity of hydrochloric acid, so that there may be no free hydrochloric
acid in the liquid. To keep back any free acetic acid which might be
swept over by the current of gas, there is introduced after the washing
apparatus another washing bottle with sodium carbonate. Also solid
potassium carbonate may be used instead of calcium chloride for drying
the gas. If the two apertures of the washing apparatus are fitted with
small pinch cocks, it is ready for use, and merely requires to be
connected with the gas apparatus in action in order to free the gas
generated from oxygen. As but little chromous salt is decomposed by the
oxygen such a washing apparatus may serve for many experiments.
* * * * *
GAIFFE'S NEW MEDICAL GALVANOMETER.
In this apparatus, which contains but one needle, and has no directing
magnet, proportionability between the intensities and deflections is
obtained by means of a special form given the frame upon which the wire
is wound.
We give herewith a figure of the curve that Mr. Gaiffe has fixed upon
after numerous experiments. Upon examination it will be seen that the
needle approaches the current in measure as the directing action of
the earth increases; and experiment proves that the two actions
counterbalance each other, and render the deflections very sensibly
proportional to the intensities up to an angle of from 65 to 75 degrees.
[Illustration]
Another important fact has likewise been ascertained, and that is that,
under such circumstances, the magnetic intensity of the needle may
change without the indications ceasing to have the same exactness up to
65 degrees. As well known, Mr. Desains has demonstrated that this occurs
likewise in sinus or tangent galvanometers; but these have helices that
are very large in proportion to the needle. In medical galvanometers the
proportions are no longer the same, and the needle is always very near
the directing helix. If this latter is square, or even elliptical, it is
found that, beyond an angle of 15 degrees, there are differences of 4 or
5 degrees in the indications given with the same intensity of current by
the same needle, according to the latter's intensity of magnetism. This
inconvenience is quite grave, for it often happens that a needle changes
magnetic intensity, either under the influence of too strong currents
sent into the apparatus, or of other magnets in its vicinity, or as
a consequence of the bad quality of the steel, etc. It was therefore
urgently required that this should be remedied, and from this point
of view the new mode of winding the wire is an important improvement
introduced into medical galvanometers.--_La Lumiere Electrique_.
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