Part 58
_Prop., Uses, &c._ Crystals, thin and nearly colourless plates, containing combined water; very soluble in hot water, less so in cold water; and rapidly decomposed by exposure to the air. It is principally used to form the BARIUM SALTS, and in organic analysis. Care should be taken in its preparation to expose the solution to the air as little as possible. SULPHIDES of a higher grade may be formed by boiling this compound with sulphur; but they possess little practical interest.
=Barium, Sulphite of.= BaSO_{3}. _Syn._ SUL'PHITE OF BARYTA. _Prep._ By testing a soluble barium salt with sodium sulphite, and washing the precipitate. Insoluble.
=Barium, Tartrate of.= BaC_{4}H_{4}O_{6}. _Syn._ TAR'TRATE OF BARYTA. _Prep._ Like that of oxalate of barium. White powder. Slightly soluble.
=BARK.= [Eng., Dan.] _Syn._ COR'TEX, L.; ÉCORCE, Fr.; BAUMRINDE, RINDE, Ger. The rind or exterior covering of vegetables, corresponding to the skin of animals. It consists of the--cu'ticle or epiderm'is--cellular substance, containing colouring matter, &c., and--li'ber, the inner or true bark. The last is formed of woody fibre in great quantity, intermixed with cellular tissue. At the commencement of the annual growth of a tree, the bark separates spontaneously from the wood, in order to make room for the new matter forming beneath. It thus increases by yearly layers, and gradually perishes on the outside, owing to distension, from the growth of the interior portion. Its physiological uses are numerous and important. It is the depository of many of the secretions of plants, and it acts as a living filter, separating secretions from each other, and allowing a part of them to pass off horizontally through the medullary processes on their way to the centre of the tree. But its principal offices appear to be to act as a protection to the tender wood, and as a channel for the sap in its descent from the leaves. "True bark only exists in exogens and gymnosperms; in endogens its place is supplied by cortical integuments, which cannot be separated from the adjacent wood, without violence." (Lindley.)
According to Liebig, the characteristic ingredients found in bark are excrementitious--"substances evidently expelled by the living organism." True wood yields only ·25% to 2% of ash; whilst the bark of some trees give 6, 10, to 15 times more; and these, like the organic constituents, differ materially in their composition and characters.
The uses of different species of bark in medicine and the arts are well known. CINCHONA-BARK is invaluable in fevers; OAK-BARK furnishes the tanner with one of the most important materials of his trade; and the tenacious fibres of other varieties are manufactured into cordage and textile fabrics.
Barks should be collected at that season in which they can be most easily separated from the wood, which, with a few exceptions, is late in the spring; because at this time the active principles deposited in their cells are most abundant. OAK-BARK, collected in spring, contains four times as much astringent matter as that collected in winter.
=Bark.= (In _medicine_.) See CINCHONA.
=Bark.= (In _tanning_.) See OAK.
=Bark, Jes'uit's.= Cinchona-bark.
=Bark, Salt of= (Essential). See EXTRACTS and SALTS.
=BAR'LEY.= _Syn._ HOR'DEUM, L.; ORGE, Fr.; GERSTE, Ger., Anglo-S. A well-known grain, the produce of several species of the genus _hordeum_.
_Var., Cult., &c._ Those principally cultivated in England are--TWO'-ROWED, LONG'-EARED, or COMM'ON BARLEY (_hor'deum dis'tichon_, Linn.); SPRING'-BARLEY, SQUARE'-B., or BERE (_h. vulga''re_, Linn.); and SIX'-ROWED BARLEY, WINTER B., Scotch BERE or BIGG (_h. hexas'tichon_, Linn.). PUT'NEY, SPRAT, or BATT'LEDORE B. (_h. zeocriton_, Linn.), is another species less frequently met with. Of each of the above there are several varieties. In Spain and Sicily, two crops of barley are obtained in a year; but, in countries so far north as Britain, it produces only one, and is a delicate species of grain. In England it is generally adopted as a succession crop on light lands, following turnips or green crops. (Loudon.) The 'yield' per acre varies from 28 to 64 bushels, and is usually from 28 to 40 bushels. The average weight per bushel is 50 to 51 _lbs._; but the best Norfolk and Essex samples weigh 53 to 54 _lbs._ per bushel.
_Comp._ The leading constituents of barley are nearly similar to those of wheat, but it is scarcely so rich in nitrogenised matter. According to Einhof, the ripe SEEDS or GRAINS are composed of--
Meal 70·05 Husk 18·75 Moisture 11·20 ------ 100·
According to Johnston, average fine BARLEY-MEAL contains--
Starch 68· Albumen, gluten, &c. 14· Fatty matter 2· Ash or saline matter 2· Water 14· ---- 100·
According to Payen, dried barley possesses the following composition--
Nitrogenous matter 12·96 Starch 66·43 Dextrin 10·00 Fatty matter 2·76 Cellulose 4·75 Mineral matter 3·10 ------ 100·00
According to Dr Ure, the sp. gr. of ENGLISH BARLEY is 1·25 to 1·33 (average, 1·235), and the weight of the husk is about 1-6th; that of BIGG, 1·227 to 1·265, and weight of husk, 2-9ths.
The analyses of the following varieties of barley, gave as the composition of the ashes of the grains:--
|Unknown |Chevalier| From |Chevalier | | Barley |Moldavia| Barley -------------+--------+---------+--------+--------- Potash | 21·14 | 20·77 | 37·55 | 7·70 Soda | | 4·56 | 1·06 | 0·36 Lime | 1·65 | 1·48 | 1·21 | 10·36 Magnesia | 7·26 | 7·45 | 10·17 | 1·26 Sesquioxide | | | | of iron | 2·13 | 0·51 | 1·02 | 1·46 Sulphuric | | | | acid | 1·91 | 0·79 | 0·27 | 2·99 Silica | 30·68 | 32·73 | 24·56 | 70·77 Phosphoric | | | | acid | 28·53 | 31·69 | 38·64 | 1·99 Chloride of | | | | Sodium | 1·10 | | 1·47 | 1·10 ---------------------------------------------------
In the 'Journal of the Agricultural Society' for 1873 is a report by Messrs Lawes and Gilbert of twenty years' experiments with barley. The soil of a field at Rothampstead, in which the barley had been grown for twenty years, consisted of heavy loam, with a subsoil of clay resting on chalk, and was previous to the barley being planted almost exhausted by cropping. The produce was found to be greatest during the absence of drought and sudden alterations of temperature, the rather cool but uniform season of 1854 giving the heaviest crops. The yield from farm-yard manure and nitrate of soda was found in dry seasons to be rather larger than that from ammonia salts. Barley manured with phosphates was found to ripen one to two weeks earlier than when the phosphate was omitted.
The average produce per acre of a few of the principal plots is given below. The "ammonium salts" are stated to be a mixture of equal parts of sulphate and chloride; the "alkali salts" consist of the sulphates of potassium, sodium, and magnesium; the "cinerials" consist of alkali salts, plus superphosphate:
KEY: A: Dressed Corn. B: Straw and Chaff. C: Total Produce. D: Corn to 100 Straw. E: Weight per Bushel of Dressed Corn. F: Produce of second 10 yrs. over or under first 10 yrs.
+--------+------+----+----+----+-------- Manures per Acre. | A | B | C | D | E | F -----------------------------+--------+------+----+----+----+-------- |bushels.| cwts.|lbs.| |lbs.|per cwt. | | | | | | Unmanured | 20 |11-3/4|2454|86·6|52·3|- 23·6 Mixed cinerials | 27-1/2 |14-3/8|3162|96·4|53·4|- 20·2 Ammonium salts, 200 lbs. | 32-1/2 |18-1/2|3919|89·2|52·1|- 9·7 Ammonium salts, 200 lbs., and| | | | | | alkali salts | 35 |20-3/4|4317|86·3|52·8|- 5·3 Ammonium salts, 200 lbs., and| | | | | | superphosphate | 47 |27-5/8|5760|86·8|53·5|+ 2·7 Ammonium salts, 200 lbs., and| | | | | | cinerials | 46-1/4 |28-1/2|5817|83·2|54·0|- ·3 Rape cake (mean 1300 lbs.) | 45-1/4 |26-7/8|5571|87·3|53·8| Farmyard manure, 14 tons | 48-1/4 |28-1/4|5933|88·5|54·3|+ 14·8 -----------------------------+--------+------+----+----+----+--------
The authors direct attention to the results obtained by using the cinerial manure alone, as illustrating the unsoundness of the old "mineral theory," according to which plants were supposed to possess a sufficient source of nitrogen in the atmosphere. They found a greater crop yielded by barley than wheat, when no manures were employed, as well as when cinerials were employed, a fact which they attribute to barley being better able than wheat to supply itself with nitrogen, notwithstanding the deeper roots of the latter. They state that with both wheat and barley the produce is slowly falling off under these circumstances. With ammonium salts alone, and with nitrate of sodium alone, there is much less falling off than when no nitrogenous manure is used. The falling off was least with the nitrate. The nitrate gives a rather larger crop for the same amount of nitrogen supplied, and they found this to hold when both nitrate and ammonia are applied with cinerials. The addition of superphosphate to ammonium salts or sodium nitrate greatly increases the produce; the further addition of potassium, sodium, and magnesium salts they found almost without effect.
The inference was that the barley had obtained an ample supply of potash from the natural soil, but an insufficient supply of phosphoric acid.
When ammonium salts are used alone, and the quantity of ammonia does not exceed 50 lbs. per acre, 3·68 lbs. of ammonia will yield an average increase of 1 bushel of corn and 63 _lbs._ of straw--total, 115 _lbs._; the extremes in 20 years were 2·25-18·05 _lbs._ When ammonium salts are applied with superphosphate, 2·21 _lbs._ of ammonia will produce the same result; the extremes were 1·47-5·36 _lbs._
Silicate of sodium had been applied for eight years and a half to half the barley plots receiving ammonia; no increase has resulted where ammonia and superphosphate are employed; but on the other three plots an increase had taken place, which, in the case of the plot receiving only ammonia and alkali salts, is very considerable.
The authors think this irregular reaction seems to show that the silicate has not produced its effect by furnishing silica to the crop, but by some reaction upon the plant-food of the soil. The rape cake supplied much more nitrogen than the ammonium salts, and also some phosphates and potash. Rape cake alone gives a better return than either ammonium salts or sodium nitrate applied alone; but when the three manures are mixed with superphosphate, the results for equal amounts of nitrogen show the rape cake to be decidedly inferior. From the above experiments it is inferred that a supply of carbonaceous matter does not increase the crop of barley.
A farm-yard manure containing about 0·64 per cent. of nitrogen supplied far more plant food than any of the other manures. On an average of twenty years it was found that about 8 lbs. of ammonia in the form of dung would produce a bushel of barley, with its equivalent of straw.
In all cases which were comparable it was found that barley appropriates more of the nitrogenous manure than wheat, save with farmyard manure. A large amount of nitrogen applied by manure is not taken up by the crop. Experiments in the barley field proved that large residues from ammonium salts and sodium nitrate show a small but distinct effect upon succeeding crops, the influence extending over many years. From an examination of the drainage waters from lands dressed with the nitrates of ammonium and sodium, the authors conclude that ammonium salts, as well as sodium nitrate, will be more economically applied in the spring than in the winter. Manures containing organic nitrogen are clearly not so liable to loss from drainage.
Experiments were made on the growth of barley after turnips, and also in an ordinary four-course rotation. After growing turnips ten years consecutively with purely cinerial manures, and carting off the produce, the yield of barley was much smaller than in the experimental field, where barley was grown after barley. The turnips, though very small crops, had exhausted the soil of nitrogen to a greater extent than corn crops would have done. On one plot where rape cake had been applied to the turnips, the produce of barley was 8-1/4 bushels more than when none had been used. In the rotation experiments barley was grown after turnips (carted off), and was followed by beans and wheat. In one series all the crops were unmanured; in another the turnips received superphosphate; in a third the turnips received an abundant cinerial and nitrogenous manure.
The mean produce of the six crops of barley obtained in twenty-four years of rotation was as follows:
|Dressed | Straw and Character of Rotation. | Corn. | Chaff. --------------------------+---------+----------- | bushels.| cwt. Unmanured continuously | 38-3/8 | 21-3/4 Superphosphate for turnips| | only | 29-3/8 | 16-1/2 Mixed manure for turnips | | only | 44-3/8 | 25-1/4 --------------------------+---------+----------- Mean produce of unmanured |} | barley in barley |} 21-1/2 | 12-1/8 field during the same |} | season |} | ------------------------------------------------
The unmanured turnips were so very small in quantity, that the barley in the first series was practically grown after a fallow; this barley, however, was a much larger crop than that grown after turnips manured with superphosphate only, the available nitrogen of the soil in this case being exhausted by the turnips.
In the last series the residue of the abundant manure applied to the turnip crop suffices to produce a good crop of barley.
_Qual., Uses, &c._ Its employment and value as food, and in the manufacture of malt, are well known. It forms good wholesome bread well adapted for persons who live luxuriously; but which, for the abstemious and the delicate, is inferior to that made of wheat, as it is rather less nutritious, and less easy of digestion, and commonly proves laxative to those unaccustomed to its use. Barley-flour and barley-meal are also more perishable than wheat-flour; being very apt to acquire a hot nauseous taste, which even the heat of the oven does not remove. In a medical point of view, barley is regarded as the mildest and least irritating of the cereals. It has always been in high estimation as a demulcent and emollient. The decoction (BAR'LEY-WATER), made with pearl barley, is a common and useful drink in inflammatory diseases, particularly in those of the chest and urinary organs. Among the Ancients, decoctions of barley ([Greek: krathê]) were the principal aliments and medicines employed in acute diseases.
Barley was extensively cultivated by the Romans and many other nations of antiquity, as well as by the ancient inhabitants of Gaul. The Greeks are said to have trained their athletes on it.
The best tests of the genuineness of barley are its colour, freedom from dust, grit, and insects. The microscope will lead to the detection of any cheaper grains if mixed with it. It is rarely adulterated, although it is said to be extensively used for the purpose of sophisticating wheat, annatto, and roll liquorice.
=Barley, Cau'stic.= Sabadilla.
=Barley, Pat'ent.= _Syn._ FARI'NA HOR'DEI, L. Pearl barley reduced to fine powder by grinding in a mill.
=Barley, Pearl.= _Syn._ PEARL'ED BARLEY*; HOR'DEUM DECORTICATUM (B. P.), L.; ORGE PERLÉ, Fr.; PERLENGRAUPEN, Ger. The seeds of _hordeum distichon_ deprived of the husks. That of commerce is usually made by steaming spring-barley, to soften the skin, then drying it, and grinding it in a mill with the stones set wide apart, so as to round and polish the grains, and to separate the whole of the husk except that left in the furrow of the seed. SCOTCH PEARL-BARLEY and FRENCH BARLEY resemble the last, but are smaller, being generally made from winter-barley or bigg. FARO DE ORZO is another variety made from sprat-barley. See BARLEY (_above_).
=Barley, Scotch.= _Syn._ HULLED BARLEY[double-dagger], POT-B.[double-dagger]; HOR'DEUM MUNDA'TUM, L.; ORGE MONDÉ, Fr.; GERSTENGRAUPEN, GRAUPEN, Ger. The grains deprived of the husk by a mill, as noticed above, but less completely, and without rounding them.
=BAR'LEY SUGAR.= See CONFECTIONERY, and SUGAR.
=BARM.= See YEAST.
=BAROM'ETER= (_baros_, weight; _metron_, measure). _Syn._ WEATHER-GLASS[double-dagger]; BAROM'ETRUM, L.; BAROMÈTRE, Fr.; BAROMETER, WETTERGLAS, Ger. An instrument for measuring the weight or pressure of the atmosphere. It was invented by Torricelli, of Florence, A.D. 1643.
The barometer is made of several forms, but the principle of its construction, with the exception of the aneroid barometer, is the same in each, and essentially consists of a column of fluid (usually mercury) supported in vacuo, in a glass tube, by the pressure of the atmosphere on its surface. The annexed figures exhibit the principal varieties at present known; several of which have been proposed with the view of improving the original instrument, either by increasing its range, or its portability. None, however, equal in simplicity, cheapness, and usefulness, the old forms proposed by Torricelli, and represented by the figs. 1 & 2. To avoid confusion, the graduated scales and cases of the instruments are not shown.
The construction of a barometer requires the utmost skill and care of a practised artist, and will therefore be seldom undertaken by the amateur or experimentalist--a fact which renders it unnecessary for us to enter into the details here. In the choice of his instrument the purchaser must greatly depend on the known experience and integrity of the manufacturer; as nothing but lengthened use, and frequent comparisons with other instruments, can possibly prove its excellence. An ordinary barometer, however carefully made, is found to suffer gradual deterioration, from the external air insinuating itself between the mercury and the glass tube, by which the perfection of the vacuum is destroyed. Various plans have been proposed to remedy this inconvenience and source of error. Prof. Daniell forms the bottom part of the tube, to the extent of about 1/3rd of an inch, of solid platinum, welded to the glass. This plan has proved completely satisfactory. Dr Ure proposes the use of platinum-foil for the same purpose. Before purchasing an instrument it is as well to ascertain that this has been done. In those called 'STANDARD BAROMETERS' the scale is movable and adjustable by a delicate screw, so as to enable the observer to bring the lower point or zero (0) of the scale coincident with the surface of the mercury in the cistern. Exact contact is readily effected by making the point, and its image as seen by reflection from the surface of the mercury, to coincide. In this case the cistern is made of glass. Provided the ivory scale be connected with the zero-point with a strip of brass, correction as to temperature is very nearly effected by this simple adjustment. The WHEEL-BAROMETER is chiefly serviceable as a domestic or land weather-glass.
Of the many forms of mercurial barometer, that perhaps known as Fortin's is the best. In this instrument the cistern and the lower portion of the tubes is shown in the annexed figure.
"The cistern is made of boxwood, with a movable leather bottom _b b_, and a glass cylinder, _b_, is inserted into it above, all except the glass being encased in brass. In the bottom of the brass box a screw, C, works on the upper end of which the leather rests, so that by elevating or depressing this screw, the bottom of the cistern, and with it the cistern level of the mercury, can also be raised or depressed at pleasure. A small ivory pin, _p_, ending in a point is fixed to the upper frame of the cistern, and when an observation is made, the surface of the mercury is made to coincide with the point of the pin as the standard level from which the barometric column is to be measured. The tube of the barometer, the upper part of which is shown in the lower figure, is enclosed in one of brass, which has two directly opposite slits in it for showing the height of the column, and on the sides of these the graduation is marked. A brass collar, _d, d_, slides upon the tube with a vernier, _v, v_, marked on it for reading the height with the greatest exactness and in which two oblong holes are cut, a little wider than the slits in the brass tube. When a reading is taken the collar is so placed that the last streak of light is cut off by the two upper edges of the holes or until they form a tangent to the convex mercurial curve. By this means the observer is sure that his eye is on a level with the top of the column and that the reading is taken exactly for this point. Fortin's barometer is generally arranged so as to be portable, in which case the screw, _c_, is sent in until the mercury fills the whole cistern, by which the air is kept from entering the tube during transport, the leather yielding sufficiently at the same time to allow for expansion for increase of temperature. It packs in a case which serves as a tripod when the instrument is mounted for use. On this tripod it is suspended about the middle, swinging upon two axles at right angles to each other, so that the cistern may act the part of a plummet, in keeping the tube vertical--the position essential to all measurements."[107]
[Footnote 107: Chambers's 'Encyclopædia.']