Cooley's Cyclopaedia of Practical Receipts Volume I Part 98

=BLIND'NESS= (blind'-). _Syn._ ABLEP'SIA, Cae'CITAS, &c., L.; AVEUGLEMENT, CeCITe, Fr.; BLINDHEIT, Ger. Deprivation or want of sight.

Blindness may be congenital, or born with a person; or it may arise from accident, external violence, or disease. In the latter it may frequently be relieved by medical and surgical treatment. See AMAUROSIS, CATARACT, EYES, OPHTHALMIA, VISION, &c.

=Blindness, Day.= _Syn._ NIGHT'-SIGHT; NY??CTALO'PIA, L. A disease of the eye in which vision is painfully acute or more or less extinct in a strong light, as that of day; but clear and pleasant in the dusk of evening and at night. Its chief causes are excessive exposure of the eyes to the direct influence of very strong or glaring light, or to heat, or both of them together; and is often one of the sequelae of ophthalmia (which _see_).

=Blindness, Night.= _Syn._ DAY'-SIGHT; HEMERALO'PIA, L. An affection of the eye, the reverse of the preceding, in which objects are clearly seen only in broad daylight. In the beginning of the complaint the patient continues to be able to see, though less clearly, for a short time after sunset, and even by moonlight, and perhaps distinctly by bright candle light; but after a short time this power is lost. It most frequently occurs in hot climates, and low lat.i.tudes at sea. Its chief causes are fatigue and exposure of the eyes to the glare of the tropical sun, probably coupled with gastric derangement. In some cases it is congenital, and is then generally incurable. The treatment consists in avoiding exciting causes, and endeavouring to restore the tone of the stomach, and the general health, by the usual methods. The eyes at the same time should be topically medicated by the frequent use of cold water, or mild astringent collyria. See OPHTHALMIA (Chronic).

=BLIS'TER.= _Syn._ PAP'ULA, PUS'TULA, L.; PUSTULE, VESSIE, &c., Fr.; BLASE, BLATTER, Ger. A bladder or vesicle caused by the deposition of serous fluid between the cuticle and the derma or true skin, occasioned by the application of a vesicant, or by a burn, scald, or friction.

=Blister.= _Syn._ VESICATO"RIUM, L.; EPISPASTIQUE, VESICATOIRE, Fr.; BLASEN-PFLASTER, B.-STOFF, Ger. A substance which vesicates or raises blisters; in pop. lang., a vesicating plaster or similar application.

The use of blisters is very ancient, and appears to date back long prior to the time of Hippocrates. Indeed, their value as cutaneous stimulants and counter-irritants appears to have been recognised by the medical faculty of all nations down to the present time. It is a principle sufficiently established with regard to the living system, that where a morbid action exists, it may often be removed by inducing an action of a different kind, as a state of excitement or irritation, in the same or a neighbouring part. In this way is explained the utility of blisters in local inflammation and spasmodic action, and it is this principle which regulates their application in pneumonia, gastritis, hepat.i.tis, phrenitis, angina, rheumatism, colic, spasmodic affections of the stomach, &c.--diseases in which they are employed with the most marked advantage. A similar principle exists with respect to pain; exciting one pain often relieves another. Hence blisters frequently give relief in neuralgia, toothache, and other like painful affections. Lastly, blisters, by their operation, communicate a stimulus to the whole system, and raise the vigour of the circulation. Hence, in part, their utility in fevers of the typhoid kind, though in such cases they are used with still more advantage to obviate or remove local inflammation.

Blisters are commonly prepared with cantharides plaster, or with some other preparation of cantharides; and, in the former case, usually have their surface sprinkled over with powdered Spanish fly; whilst the blistering surface is surrounded with a margin spread with common adhesive plaster, for the purpose of causing them to adhere to the part to which they are applied. In order to prevent the action of the cantharides upon the mucous membrane of the bladder, or urinary organs, they are also often sprinkled with a little powdered camphor, or better still, are moistened with camphorated ether, which, on its evaporation, leaves a thin layer of camphor on the surface; but care must be taken that the layer be not too thick, as in that case the plaster would not take effect. With a like object, a piece of thin book-muslin or tissue-paper (silver-paper) is frequently placed between the blistering surface of the plaster and the skin; the efficacy of which may be still further heightened by first soaking the muslin or paper in olive or almond oil.

The usual time an ordinary blister of cantharides plaster is allowed to remain in contact with the skin is from 10 to 12 hours. It is then gently removed. The subsequent treatment depends on the object in view. When it is not wished to maintain a discharge from the blistered surface, the vesicle is cut with the point of a pair of scissors at its most depending part, to let out the fluid which it contains, followed by a dressing of spermaceti or other simple ointment; but when the case requires the blister to be kept open, or to be converted into a perpetual blister, as it is sometimes called, the whole of the detached cuticle is carefully removed with the scissors, and the part is dressed with either the ointment of cantharides or of savine, at first more or less diluted with lard or simple ointment, with an occasional dressing of resin cerate.

According to Mr Crowther, the blistered surface is best kept clean by daily fomentation with warm water.

Of late years, to obviate the unpleasant effects occasionally arising from the common blister, various compounds having cantharides for their base, as well as fabrics spread with them, have been brought before the public.

These are noticed hereafter. See PLASTER, VESICANTS, &c.

=Blisters, Extempora"neous.= Among the best of these may be mentioned the following:--

1. A piece of lint dipped in the strongest vinegar of cantharides, and immediately after its application to the skin, covered over with a piece of strapping, or preferably a piece of sheet gutta percha or oiled silk, to prevent evaporation. Raises a blister in from 5 to 8 minutes.

2. Concentrated acetic acid, applied in the same way, has a similar effect.

3. (Dr Darcq.) Into a flat watch gla.s.s pour from 8 to 10 drops of highly concentrated liquor of ammonia; cover the liquid with a small piece of linen of rather less diameter than that of the gla.s.s, and at once apply this little apparatus to the previously shaved skin. The whole must be kept in its place by means of moderate pressure with the fingers, until a red ring, about 2 centimetres in breadth, is observed round the gla.s.s, when it is certain that vesication is effected. Sometimes scarcely 30 seconds are necessary for obtaining the result. The apparatus may then be removed, and the blistered part treated in the usual manner; the dressing being according to the object in view.

4. (Trousseau.) Bibulous paper slightly wetted with a little of the ethereal extract of cancharides, and instantly applied to the skin, the whole being covered with a piece of common adhesive plaster to prevent evaporation.

5. Boiling water applied by means of a suitably shaped tube, the adjacent parts being at the same time protected from injury. Instantaneous.

=Blister, Horse.= See VETERINARY MEDICINES.

=Blister*, Perpet'ual.= See BLISTER (_ante_).

=BLIS'TERING.= _Syn._ VES'ICANS, VESICATO"RIUS, L.; EPISPASTIQUE, VeSICANT, VeSICATOIRE, Fr.; BLASENZIEHEND, &c., Ger. In _medicine_, &c., that vesicates or raises blisters when applied to the skin.

=Blistering Pa'per, Plas'ter, Tis"sue= (tish-u), &c. See PLASTERS, VESICANTS, &c.

=BLOAT'ER.= See BLOTE.

=BLONDE.= [Fr.] _Syn._ BLOND'-LACE. Silk-lace. The name is now also applied to cotton-lace edged with silk. For the mode of cleaning it and getting it up, see LACE and MUSLIN.

=BLOOD= (blud). _Syn._ SAN"GUIS, L.; SANG, Fr.; BLUT, Ger. The general circulating fluid of animals, and that on which the nourishment and growth of their bodies depend, and from which all the secretions are formed. It is warm and red in vertebrated animals; and, for the most part, cold and white in the invertebrata. In man and all other mammals, and in birds--the two highest cla.s.ses of the animal kingdom--the blood, though collectively forming but one circulating stream, varies considerably in appearance according to the part or vessels in which it is found. That contained in the left side of the heart, and in the arteries, possesses a very brilliant scarlet colour, and is called arte"rial blood; whilst that found in the right side of the heart, and in the veins, has a darkish purple colour, and is called ve'nous blood. The two, however, differ little from each other in their chemical properties and composition; the most marked point of difference being that venous blood holds carbonic acid in solution, whilst oxygen predominates in the blood of the arteries.

The fibrine of venous blood is also soluble in a solution of nitrate of pota.s.sa; whilst that of arterial blood is insoluble in that menstruum.

_Comp._ Blood consists of a transparent and nearly colourless fluid (plas'ma, se"rum, seralbu'men), in which float about a countless mult.i.tude of microscopic round red bodies (blood-discs, blood-corpuscles), to which its colour is due, accompanied by a few colourless globules (white blood-corpuscles) of a somewhat larger size. The red corpuscles are found, on more minute examination, to consist of an envelope containing a solution of haematosin.

_Prop._ These are, for the most part, well known. It has an alkaline reaction, a saline and rather disagreeable sweetish taste, and when newly drawn evolves a peculiar odour or halitus, which almost immediately disappears. As it cools and on repose it coagulates, owing, according to some, to the spontaneous solidification of the fibrine.

The following table, based upon the observations of Schmidt and the a.n.a.lysis of Lehmann, is given by the latter, as representing the average quant.i.tative relation of the princ.i.p.al const.i.tuents of normal blood. It will be noticed that the blood is here regarded as composed of two portions, one consisting solely of the red particles, and the other of the liquid, in which these red corpuscles are suspended, termed the _liquor sanguinis_, which consists of the serum holding fibre in solution:--

_Sp. gr. of Blood-corpuscles, 10885._

1000 parts blood-corpuscles contain--

Water 68800 Solid const.i.tuents 31200 consisting of-- Haematin (with iron) 1675 Globulin and cell membrane 28222 Fat 231 Extractive matters 260 Mineral substances (without iron) 812 Chlorine 1686 Sulphuric anhydride (SO_{3}) 0066 Phosphoric anhydride (P_{2}O_{5}) 1134 Pota.s.sium 3328 Sodium 1052 Oxygen 0667 Calcium phosphate 0114 Magnesium phosphate 0073

_Sp. gr. of Liquor Sanguinis, 1028._

1000 parts of liquor sanguinis contain--

Water 90290 Solid const.i.tuents 9710 consisting of-- Fibrin 405 Alb.u.men 7884 Fat 172 Extractive matters 394 Mineral substances 855 Chlorine 3644 Sulphuric anhydride (SO_{3}) 0115 Phosphoric anhydride (P_{2}O_{5}) 0191 Pota.s.sium 0323 Sodium 3341 Oxygen 0403 Calcium phosphate 0311 Magnesium phosphate 0222

The ash of blood contains about 684 per cent. of ferric oxide. (Lehmann.)

The following table gives the results of the average composition of human blood in man and woman, according to the a.n.a.lyses of Becquerel and Rodie:

Male. Female.

Specific gravity of defibrinated blood 10600 10575 " " of serum 10280 10274 Water 77900 79100 Fibrin 220 220 { Serolin } { 002 } { 002 { Phosphorised fat } { 049 } { 046 Fatty Matters { } 160 { } 162 { { Cholesterin } { 009 } { 009 { Saponified fat } { 100 } { 105 Alb.u.men 6940 7050 Blood-corpuscles 14110 12720 Extractive matters 680 740 ------- ------- 100010 100002 ------- ------- { Sodium chloride 310 390 Salts { Other soluble salts 250 290 { Earthy phosphates 033 035 Metallic iron 057 054 ----- ----- 650 769

The blood also contains, in solution, oxygen, nitrogen, carbonic acid, as well as a free alkaline carbonate, urea, and small traces of alcohol have also been detected in normal blood.

The following report of a commission composed of MM. Mialhe, Mayel, Lefort, and Cornil, appointed to devise the best method for the examination of blood stains, was published in 1873. The following translation of the report appeared in the 'Chemical News' of December 5th, 1873.

1st. When the stain is of recent date, or supposed to be so, the red corpuscles should be particularly examined, and every care taken to preserve them without change. The stains must not be washed with water, so that the haematin may not be altered. After insisting on the microscopic characters of the blood stains, isolated or compared with those of various animals, the commission enumerates with care the fluids which are destructive or preservative of blood-corpuscles. Among the first, water, and particularly hot water, acetic, gallic, hydrochloric, and sulphuric acids; and of alkalies, potash and soda, even in weak solution, and ether and chloroform, also many other reagents, so alter the blood-corpuscles as to cause them to entirely disappear. Alcohol, chromic and picric acids, and b.i.+.c.hromate of potash, preserve the corpuscles, though they alter their form. The preservative fluids are those whose composition approaches nearest to serum, such as the iodised serum of Schultze, an excellent preparation made with amniotic fluid, to which are added a few drops of the tincture of iodine, so as to give it the colour of white wine; or, better, a fluid composed thus; white of egg, 30 grams; distilled water, 270 grams; and chloride of sodium, 40 grams; or even a fluid containing 05 per cent. of chloride of sodium, or 5 or 6 per cent. of sulphate of sodium. If the stains be wetted and softened by these fluids, and then examined, white and red corpuscles and fibroid particles will be observed.

2nd. In more difficult cases, when the microscope, owing to the alterations which time has effected in the haematin, can give but vague information, examination by the spectroscope and chemical a.n.a.lysis enables us to arrive at precise results. The use of these means being less known, and also more delicate, requires special study.

1. _Spectrum a.n.a.lysis._ Colouring matters have the power of absorbing certain coloured rays of white light--the same always for the same substance. This is the principle upon which spectroscopic examination is based. If into any a.n.a.lysing tube filled with water a few drops of solution of haemoglobin be introduced, till it has the colour of peach-blossoms, the luminous rays of the spectrum pa.s.sing through this fluid present two bands of absorption, in the lines D and E of Frauenhofer, in the yellow and the green. The same fact would be observed if a few drops of blood were subst.i.tuted for haemoglobin in the a.n.a.lysis.

In a case of doubt the haemoglobin of the blood could be reduced by adding to this latter a reducing body. Destroyed haemoglobin has a different spectrum from oxygenated haemoglobin, a single absorption band as large as the two former bands united, and a little to the left of Frauenhofer's line D.

2. In blood in a state of decomposition, or which has been treated with acids or caustic alkalies, haemoglobin is changed into a new substance; haematin is formed, which, combined with hydrochloric acid, gives definite crystals.

In order to obtain them we must proceed thus:--A small fragment of dried blood is placed on a gla.s.s slide; it is dissolved in a drop of water, and a minute portion of sea-salt added. It is covered with a thin slide, and pure acetic acid is made to pa.s.s between the two slides, and it is heated over a spirit-lamp to boiling-point; acetic acid is again added, and it is heated afresh; and this is repeated till the crystals are obtained.

They are rhomboidal, of a dirty brown colour, quite characteristic, and require to be seen with a magnifying power of three hundred or four hundred diameters. With the smallest quant.i.ty of blood these two reactions can always be produced--the spectrum examination and the crystals of hydrochlorate of haematin; and they are so certain that the existence of one alone enables one to affirm the presence of blood.

3. The third process, though not so exact as the preceding, ought, nevertheless, never to be neglected. If to a very small quant.i.ty of blood dissolved in a little water be added a few drops of tincture of guaiac.u.m and of binoxide of hydrogen, a persistent blue colour is immediately produced; but this very sensitive reaction can be obtained with other organic matter, such as nasal mucus, saliva, &c.; it therefore only gives a probability. We must proceed in the following manner:--A tincture of guaiac.u.m is prepared with alcohol at 83 degrees, and guaiac.u.m resin; a mixture of sulphuric ether and binoxide of hydrogen is also made, and enclosed in a stoppered bottle, and kept under water in the dark. This preparation is less liable to change than pure oxygenated waters. The object stained with blood, if it be white, is put into a little cup, then moistened with water to dissolve out the blood stain, and washed in distilled water; this water is then submitted to the action of these reagents.

If the thing stained be coloured, and the stain little or not at all visible, it must be moistened, and then pressed between two or three sheets of white blotting-paper, and tried first with the guaiac.u.m. If the stain be of blood a reddish or brown spot will form on the paper.

One of the sheets should be treated with ammonia, and the stain will become crimson or green. A second sheet treated with tincture of guaiac.u.m and ozonised ether will give a blue colour more or less intense, according to the quant.i.ty of the blood.

To recapitulate:--1. If the stains or scales of blood appear recent, the corpuscles may, after the necessary precautions, be examined under the microscope, and their presence, diameter, &c. observed, which will enable one to diagnose the origin of the blood, whether human or animal. 2. If the stains be old and the blood changed, the reaction with the tincture of guaiac.u.m would make the presence of blood probable; but its actual presence cannot be affirmed without spectrum examination or the production of crystals of hydrochlorate of haematin; one of the two is sufficient. It is unnecessary to add that these reactions do not show whether the blood is human or animal.