Edible Oils.
—With the exception of cottonseed oil, the adulterants ordinarily used with edible oils are of such a nature that the experience of a chemist and the facilities of a chemical laboratory are essential to their detection. There is, however, a simple test for the detection of cottonseed oil, known as the Halphen test, which may be readily applied.

Great care must be taken in the manipulation of this test, as one of the reagents employed—carbon bisulphide—is very inflammable. The chemicals employed in the preparation of the reagent used for this test are not household articles. They may, however, be obtained in any pharmacy. The mixture should be prepared by a druggist rather than by an inexperienced person who desires to use it.

In order to perform the test 2 or 3 ta­ble­spoon­fuls of this reagent are mixed in a bottle with an equal volume of the suspected sample of oil and heated in a vessel of boiling salt solution (prepared by dissolving 1 ta­ble­spoon­ful of salt in a pint of water) for 10 or 15 minutes. At the end of that time, if even a small percentage of cottonseed oil be present, the mixture will be of a distinct reddish color, and if the sample consists largely or entirely of cottonseed oil, the color will be deep red.

Eggs.
—There is no better method for the testing of the freshness of an egg than the familiar one of “candling,” which has long been practiced by dealers. The room is darkened and the egg held between the eye and a light; the presence of dark spots indicates that the egg is not perfectly fresh, one that is fresh presenting a homogeneous, translucent appearance. Moreover, there is found in the larger end of a fresh egg, between the shell and the lining membrane, a small air cell which, of course, is distinctly transparent. In an egg which is not perfectly fresh this space is filled and hence presents the same appearance as the rest of the egg.

It is now a matter of considerable importance to be able to distinguish between fresh eggs and those that have been packed for a considerable time. Until recently that was not a difficult matter. All of the solutions that were formerly extensively used for that purpose gave the shell a smooth, glistening appearance which is not found in the fresh egg. This characteristic, however, is of less value now than formerly, owing to the fact that packed eggs are usually preserved in cold storage. There is now no means by which a fresh egg can be distinguished from a packed egg without breaking it. Usually in eggs that have been packed for a considerable time the white and yolk slightly intermingle along the point of contact, and it is a difficult matter to separate them. Packed eggs also have a tendency to adhere to the shell on one side and when opened frequently have a musty odor.

Flavoring Extracts.

Although a large number of flavoring extracts are on the market, vanilla and lemon extracts are used so much more commonly than other flavors that a knowledge of their purity is of the greatest importance. Only methods for the examination of those two products will be considered.

Vanilla Extract.
—Vanilla extract is made by extracting vanilla beans with alcohol. It consists of an alcoholic solution of vanillin (the characteristic flavoring matter of the vanilla bean) and several other products, chiefly rosins, which, though present in but small amount and having only a slight flavor in themselves, yet affect very materially {356} the flavor of the product. Vanilla extract is sometimes adulterated with the extract of the Tonka bean. This extract, to a certain extent, resembles vanilla extract. The extract of the Tonka bean, however, is far inferior to that of the vanilla bean. It has a relatively penetrating, almost pungent odor, standing in sharp contrast to the flavor of the vanilla extract. This odor is so different that one who has given the matter some attention may readily distinguish the two, and the quality of the vanilla extract may often be judged with a fair degree of accuracy by means of the odor alone.

Another form of adulteration, and one that is now quite prevalent, is the use of artificial vanillin in place of the extract of either vanilla or Tonka beans. Artificial vanillin has, of course, the same composition and characteristics as the natural vanillin of the vanilla bean. Extracts made from it, however, are deficient in the rosins and other products which are just as essential to the true vanilla, as is vanillin itself. Since vanillin is thus obtained from another source so readily, methods for the determination of the purity of vanilla extract must depend upon the presence of other substances than vanillin.

Detection of Caramel.—The coloring matter of vanilla extract is due to substances naturally present in the vanilla bean and extracted therefrom by alcohol. Artificial extracts made by dissolving artificial vanillin in alcohol contain no color of themselves, and to supply it caramel is commonly employed. Caramel may be detected in artificial extracts by shaking and observing the color of the resulting foam after a moment’s standing. The foam of pure extracts is colorless. If caramel is present a color persists at the points of contact between the bubbles until the last bubble has disappeared. The test with fuller’s earth given for caramel in vinegar is also very satisfactory, but of course requires the loss of the sample used for the test.

Examination of the Rosin.—If pure vanilla extract be evaporated to about one-third its volume the rosins become insoluble and settle to the bottom of the dish. Artificial extracts remain clear under the same conditions. In examining vanilla extract the character of these rosins is studied. For this purpose a dish containing about an ounce of the extract is placed on a teakettle or other vessel of boiling water until the liquid evaporates to about one-third or less of its volume. Owing to the evaporation of the alcohol the rosins will then be insoluble. Water may be added to restore the liquid to approximately its original volume. The rosin will then separate out as a brown flocculent precipitate. A few drops of hydrochloric acid may be added and the liquid stirred and the insoluble matter allowed to settle. It is then filtered and the rosin on the filter paper washed with water. The rosin is then dissolved in a little alcohol, and to 1 portion of this solution is added a small particle of ferric alum, and to another portion a few drops of hydrochloric acid, If the rosin be that of the vanilla bean, neither ferric alum nor hydrochloric acid will produce more than a slight change of color. With rosins from most other sources, however, one or both of these substances yield a distinct color change.

For filtering, a piece of filter paper should be folded once through the middle and again at right angles to the first fold. It may now be opened with one fold on one side and three on the other and fitted into a glass funnel. When the paper is folded in this manner the precipitated rosins may be readily washed with water. When the washing is completed the rosins may be dissolved by pouring alcohol through the filter. This work with the rosins will require some practice before it can be successfully performed. It is of considerable value, however, in judging of the purity of vanilla extract.

Lemon Extract.
—By lemon extract is understood a solution of lemon oil in strong alcohol. In order to contain as much lemon oil as is supposed to be found in high-grade extracts the alcohol should constitute about 80 per cent of the sample. The alcohol is therefore the most valuable constituent of lemon extract, and manufacturers who turn out a low-grade product usually do so because of their economy of alcohol rather than of lemon oil. Owing to the fact that lemon extract is practically a saturated solution of oil of lemon in strong alcohol the sample may be examined by simple dilution with water. A teaspoonful of the oil in question may be placed in the bottom of an ordinary glass tumbler and 2 or 3 teaspoonfuls of water added. If the sample in question be real lemon extract the lemon oil should be thrown out of solution by reason of its insolubility in the alcohol after its dilution with water. The result is at first a marked turbidity and later the separation of the oil of lemon on the top {357} of the aqueous liquid. If the sample remains perfectly clear after the addition of water, or if a marked turbidity is not produced, it is a low-grade product and contains very little, if any, oil of lemon.
Fruit Products.
—Adulteration of fruit products is practically confined to jellies and jams. Contrary to the general belief, gelatin is never used in making fruit jelly. In the manufacture of the very cheapest grade of jellies starch is sometimes employed. Jellies containing starch, however, are so crude in their appearance that the most superficial inspection is sufficient to demonstrate that they are not pure fruit jellies. From their appearance no one would think it worth while to examine them to determine their purity.

Natural fruit jellies become liquid on being warmed. A spoonful dissolves readily in warm water, although considerable time is required with those that are especially firm. The small fruits contain practically no starch, as apples do, and the presence of starch in a jelly indicates that some apple juice has probably been used in its preparation.

Detection of Starch.—Dissolve a teaspoonful of jelly in a half teacupful of hot water, heat to boiling and add, drop by drop, while stirring with a teaspoon, a solution of potassium permanganate until the solution is almost colorless. Then allow the solution to cool and test for starch with tincture of iodine, as directed later. Artificially colored jellies are sometimes not decolorized by potassium permanganate. Even without decolorizing, however, the blue color can usually be seen.

Detection of Glucose.—For the detection of glucose, a teaspoonful of the jelly may be dissolved in a glass tumbler or bottle in 2 or 3 ta­ble­spoon­fuls of water. The vessel in which the jelly is dissolved may be placed in hot water if necessary to hasten the solution. In case a jam or marmalade is being examined, the mixture is filtered to separate the insoluble matter. The solution is allowed to cool, and an equal volume or a little more of strong alcohol is added. If the sample is a pure fruit product the addition of alcohol causes no precipitation, except that a very slight amount of proteid bodies is thrown down. If glucose has been employed in its manufacture, however, a dense white precipitate separates and, after a time, settles to the bottom of the liquid.

Detection of Foreign Seeds.—In addition to the forms of adulteration to which jellies are subject, jams are sometimes manufactured from the exhausted fruit pulp left after removing the juice for making jelly. When this is done residues from different fruits are sometimes mixed. Exhausted raspberry or blackberry pulp may be used in making “strawberry” jam and vice versa. Some instances are reported of various small seeds, such as timothy, clover, and alfalfa seed, having been used with jams made from seedless pulp.

With the aid of a small magnifying glass such forms of adulteration may be detected, the observer familiarizing himself with the seeds of the ordinary fruits.

Detection of Preservatives and Colors.—With jellies and jams salicylic and benzoic acids are sometimes employed. They may be detected by the methods given.

Artificial colors, usually coal-tar derivatives, are sometimes used and may be detected as described.

Meat Products.
—As in many other classes of foods, certain questions important in the judgment of meats require practical experience and close observation rather than chemical training. This is especially true of meat products. The general appearance of the meat must largely guide the purchaser. If, however, the meat has been treated with preservatives and coloring matter its appearance is so changed as to deceive him. The preservatives employed with meat products are boric acid, borax, and sulphites. The methods for the detection of sulphites are not suitable for household use.

Detection of Boric Acid and Borax.—To detect boric acid (if borax has been used the same reaction will be obtained), about a ta­ble­spoon­ful of the chopped meat is thoroughly macerated with a little hot water, pressed through a bag, and 2 or 3 ta­ble­spoon­fuls of the liquid placed in a sauce dish with 15 or 20 drops of strong hydrochloric acid for each ta­ble­spoon­ful. The liquid is then filtered through filter paper, and a piece of turmeric paper dipped into it and dried near a lamp or stove. If boric acid or borax were used for preserving the sample, the turmeric paper should be changed to a bright cherry-red color. If too much hydrochloric acid has been employed a dirty brownish-red color is obtained, which interferes with the color due to the presence of {358} boric acid. When a drop of household ammonia is added to the colored turmeric paper, it is turned a dark green, almost black color, if boric acid is present. If the reddish color, however, was caused by the use of too much hydrochloric acid this green color does not form.

Caution.—The corrosive nature of hydrochloric acid must not be forgotten. It must not be allowed to touch the flesh, clothes, or any metal.

Detection of Colors.—The detection of coloring matter in sausage is often a difficult matter without the use of a compound microscope. It may sometimes be separated, however, by macerating the meat with a mixture of equal parts of glycerine and water to which a few drops of acetic or hydrochloric acid have been added. After macerating for some time the mixture is filtered and the coloring matter detected by means of dyeing wool in the liquid thus obtained.

Spices.
—Although ground spices are very frequently adulterated, there are few methods that may be used by one who has not had chemical training, and who is not skilled in the use of a compound microscope, for the detection of the adulterants employed. The majority of the substances used for the adulteration of spices are of a starchy character. Unfortunately for our purposes, most of the common spices also contain a considerable amount of starch. Cloves, mustard, and cayenne, however, are practically free from starch, and the presence of starch in the ground article is proof of adulteration.

Detection of Starch in Cloves, Mustard, and Cayenne.—A half teaspoonful of the spice in question is stirred into half a cupful of boiling water, and the boiling continued for 2 or 3 minutes. The mixture is then cooled. If of a dark color, it is diluted with a sufficient amount of water to reduce the color to such an extent that the reaction formed by starch and iodine may be clearly apparent if starch be present. The amount of dilution can only be determined by practice, but usually the liquid must be diluted with an equal volume of water, or only 1/4 of a teaspoonful of the sample may be employed originally. A single drop of tincture of iodine is now added. If starch is present, a deep blue color, which in the presence of a large amount of starch appears black, is formed. If no blue color appears, the addition of the iodine tincture should be continued, drop by drop, until the liquid shows by its color the presence of iodine in solution.

Detection of Colors.—Spice substitutes are sometimes colored with coal-tar colors. These products may be detected by the methods given.

Vinegar.
—A person thoroughly familiar with vinegar can tell much regarding the source of the article from its appearance, color, odor, and taste.

If a glass be rinsed out with the sample of vinegar and allowed to stand for a number of hours or overnight, the odor of the residue remaining in the glass is quite different with different kinds of vinegar. Thus, wine vinegar has the odor characteristic of wine, and cider vinegar has a peculiar fruity odor. A small amount of practice with this test enables one to distinguish with a high degree of accuracy between wine and cider vinegars and the ordinary substitutes.

If a sample of vinegar be placed in a shallow dish on a warm stove or boiling teakettle and heated to a temperature sufficient for evaporation and not sufficient to burn the residue, the odor of the warm residue is also characteristic of the different kinds of vinegar. Thus, the residue from cider vinegar has the odor of baked apples and the flavor is acid and somewhat astringent in taste, and that from wine vinegar is equally characteristic. The residue obtained by evaporating vinegar made from sugar-house products and from spirit and wood vinegar colored by means of caramel has the peculiar bitter taste characteristic of caramel.

If the residue be heated until it begins to burn, the odor of the burning product also varies with different kinds of vinegar. Thus, the residue from cider vinegar has the odor of scorched apples, while that of vinegars made from sugar-house wastes and of distilled and wood vinegars colored with a large amount of caramel has the odor of burnt sugar. In noting these characteristics, however, it must be borne in mind that, in order to make them conform to these tests, distilled and wood vinegars often receive the addition of apple jelly.

The cheaper forms of vinegar, especially distilled and wood vinegar, are commonly colored with caramel, which can be detected by the method given.

Food Colorants.

(Most, if not all, of these colorants are injurious and should therefore be used with extreme caution.)

Sausage Color.
—To dye sausage red, certain tar dyestuffs are employed, {359} especially the azo dyes, preference being given to the so-called genuine red. For this purpose about 100 parts of dyestuff are dissolved in 1,000 to 2,000 parts of hot water; when the solution is complete, add a likewise hot solution of 45 to 50 parts of boracic acid, whereupon the mixture should be stirred well for some time; then filter, allow to cool, and preserve in tightly closing bottles. It is absolutely necessary in using aniline colors to add a disinfectant to the dyestuff solution, the object of which is, in case the sausage should commence to decompose, to prevent the decomposition azo dyestuff by the disengaged hydrogen. Instead of boracic acid, formalin may be used as a disinfectant. Of this formalin, 38 per cent, add about 25 to 30 parts to the cooled and filtered dyestuff solution. This sausage color is used by adding about 1 1/2 to 2 ta­ble­spoon­fuls of it to the preserving salt measured out for 100 kilos of sausage mass, stirring well. The sausage turns neither gray nor yellow on storing.
Cheese Color.
—I.—To produce a suitable, pretty yellow color, boil 100 parts of orlean or annatto with 75 parts of potassium carbonate in 1 1/2 to 2 liters of water, allow to cool, and filter after settling, whereupon 15 to 18 parts of boracic acid are added to give keeping qualities to the solution. According to another method, digest about 200 parts of orlean, 200 parts of potassium carbonate, and 100 parts of turmeric for 10 to 12 days in 1,500 to 2,000 parts of 60 per cent alcohol, filter, and keep in bottles. To 100,000 parts of milk to be made into cheese add 1 1/2 to 2 small spoonfuls of this dye, which imparts to the cheese a permanent and natural yellow appearance.

II.—To obtain a handsome yellow color for cheese, such as is demanded for certain sorts, boil together 100 parts of annatto and 75 parts of potassium carbonate in from 1,500 to 2,000 parts of pure water; let it cool, stand it aside for a time, and filter, adding finally from 12 to 15 parts of boracic acid as a preservative. For coloring butter, there is in the trade a mixture of bicarbonate of soda with 12 per cent to 15 per cent of sodium chloride, to which is added from 1 1/2 per cent to 2 per cent of powdered turmeric.

Butter Color.
—For the coloring of butter there is in the market under the name of butter powder a mixture of sodium bicarbonate with 12 to 15 per cent of sodium chloride and 1 1/2 to 2 per cent of powdered turmeric; also a mixture of sodium bicarbonate, 1,500 parts; saffron surrogate, 8 parts; and salicylic acid, 2 parts. For the preparation of liquid butter color use a uniform solution of olive oil, 1,500 parts; powdered turmeric, 300 parts; orlean, 200 parts. The orlean is applied on a plate of glass or tin in a thin layer and allowed to dry perfectly, whereupon it is ground very fine and intimately mixed with the powdered turmeric. This mixture is stirred into the oil with digestion for several hours in the water bath. When a uniform, liquid mass has resulted, it is filtered hot through a linen filter with wide meshes. After cooling, the filtrate is filled into bottles. Fifty to 60 drops of this liquid color to 1 1/2 kilos of butter impart to the latter a handsome golden yellow shade.

Infant Foods:

Infants’ (Malted) Food.—

I.— Powdered malt 1 ounce
Oatmeal (finest ground) 2 ounces
Sugar of milk 4 ounces
Baked flour 1 pound

Mix thoroughly.

II.—Infantine is a German infant food which is stated to contain egg albumen, 5.5 per cent; fat, 0.08 per cent; water, 4.22 per cent; carbohydrates, 86.58 per cent (of which 54.08 per cent is soluble in water); and ash, 2.81 per cent (consisting of calcium, 10.11 per cent; potassium, 2.64 per cent; sodium, 25.27 per cent; chlorine, 36.65 per cent; sulphuric acid, 3.13 per cent; and phosphoric acid, 18.51 per cent).

Meat Preservatives.

(Most of these are considered injurious by the United States Department of Agriculture and should therefore be used with extreme caution.)

The Preservation Of Meats.
—Decomposition of the meat sets in as soon as the blood ceases to pulse in the veins, and it is therefore necessary to properly preserve it until the time of its consumption.

The nature of preservation must be governed by circumstances such as the kind and quality of the article to be preserved, length of time and climatic condition, etc. While salt, vinegar, and alcohol merit recognition on the strength of a long-continued usage as preservatives, modern usage favors boric acid and borax, and solutions containing salicylic acid and sulphuric acid are common, {360} and have been the subject of severe criticism.

Many other methods of preservation have been tried with variable degrees of success; and of the more thoroughly tested ones the following probably include all of those deserving more than passing mention or consideration.

1. The exclusion of external, atmospheric electricity, which has been observed to materially reduce the decaying of meat, milk, butter, beer, etc.

2. The retention of occluded electric currents. Meats from various animals packed into the same packages, and surrounded by a conducting medium, such as salt and water, liberate electricity.

3. The removal of the nerve centers. Carcasses with the brains and spinal cord left therein will be found more prone to decomposition than those wherefrom these organs have been removed.

4. Desiccation. Dried beef is an excellent example of this method of preservation. Other methods coming under this heading are the application of spices with ethereal oils, various herbs, coriander seed extracted with vinegar, etc.

5. Reduction of temperature, i. e., cold storage.

6. Expulsion of air from the meat and the containers. Appert’s, Willaumez’s, Redwood’s, and Prof. A. Vogel’s methods are representative for this category of preservation. Phenyl paper, Dr. Busch’s, Georges’s, and Medlock and Baily’s processes are equally well known.

7. The application of gases. Here may be mentioned Dr. Gamgee’s and Bert and Reynoso’s processes, applying carbon dioxide and other compressed gases, respectively.

Air-drying, powdering of meat, smoking, pickling, sugar or vinegar curing are too well known to receive any further attention here. Whatever process may be employed, preference should be given to that which will secure the principal objects sought for, the most satisfactory being at the same time not deleterious to health, and of an easily applicable and inexpensive nature.

To Preserve Beef, Etc., In Hot Weather.
—Put the meat into a hot oven and let it remain until the surface is browned all over, thus coagulating the albumen of the surface and inclosing the body of the meat in an impermeable envelope of cooked flesh. Pour some melted lard or suet into a jar of sufficient size, and roll the latter around until the sides are evenly coated to the depth of half an inch with the material. Put in the meat, taking care that it does not touch the sides of the jar (thus scraping away the envelope of grease), and fill up with more suet or lard, being careful to completely cover and envelop the meat. Thus prepared, the meat will remain absolutely fresh for a long time, even in the hottest weather. When required for use the outer portion may be left on or removed. The same fat may be used over and over again by melting and retaining in the melted state a few moments each time, by which means not only all solid portions of the meat which have been retained fall to the bottom, but all septic microbes are destroyed.
Meat Preservatives.
—I.—Barmenite Corning Agent: For every 100 parts, by weight, take 25.2 parts, by weight, of saltpeter; 46.8 parts, by weight, sodium chloride; 25.7 parts, by weight, cane sugar; 0.8 parts, by weight, plaster of Paris or gypsum; 0.1 part, by weight, of some moistening material, and a trace of magnesia.

II.—Carniform, A: For every 100 parts, by weight, take 3.5 parts, by weight, sodium diphosphate; 3.1 parts, by weight, water of crystallization; 68.4 parts, by weight, sodium chloride; 24.9 parts, by weight, saltpeter; together with traces of calcium phosphate, magnesia, and sulphuric acid.

III.—Carniform, B: For every 100 parts, by weight, take 22.6 parts, by weight, sodium diphosphate; 17.3 parts, by weight, water of crystallization; 59.7 parts, by weight, saltpeter; 0.6 parts, by weight, calcium phosphate; with traces of sulphuric acid and magnesia.

IV.—“Cervelatwurst” (spice powder): For 100 parts, by weight, take 0.7 parts, by weight, of moistening; 3.5 parts, by weight, spices—mostly pepper; 89 parts, by weight, sodium chloride; 5 parts, by weight, saltpeter; 0.7 parts, by weight, gypsum; and traces of magnesia.

V.—Cervelatwurst Salt (spice powder): For 100 parts, by weight, take 7.5 parts, by weight, spices—mostly pepper; 1.6 parts, by weight, moistener; 81.6 parts, by weight, sodium chloride; 2.5 parts, by weight, saltpeter; 6.2 parts, by weight, cane sugar; and traces of magnesia.

VI.—Rubrolin Sausage (spice powder): For 100 parts by weight, take 53.5 parts, by weight, sal ammoniac, and 45.2 parts, by weight, of saltpeter.

VII.—Servator Special Milk and Butter Preserving Salt: 80.3 per cent of crystallized boracic acid; 10.7 per cent {361} sodium chloride; and 9.5 per cent of benzoic acid. (Its use is, however, prohibited in Germany.)

VIII.—Wittenberg Pickling Salt: For 100 parts, by weight, take 58.6 parts, by weight, sodium chloride; 40.5 parts, by weight, saltpeter; 0.5 parts, by weight, gypsum; traces of moisture and magnesia.

IX.—Securo: For a quart take 3.8 parts, by weight, aluminum oxide, and 8 parts, by weight, acetic acid; basic acetate of alumina, 62 parts, by weight; sulphuric acid, 0.8 parts, by weight; sodium oxide, with substantially traces of lime and magnesia.

X.—Michels Cassala Salt: This is partially disintegrated. 30.74 per cent sodium chloride; 15.4 per cent sodium phosphate; 23.3 per cent potassio-sodic tartrate; 16.9 per cent water of crystallization; 1.2 per cent aluminum oxide; and 2.1 per cent acetic acid as basic acetate of alumina; 8.4 per cent sugar; 0.98 per cent benzoic acid; 0.5 per cent sulphuric acid; and traces of lime.

XI.—Corning Salt: Sodium nitrate, 50 parts; powdered boracic acid, 45 parts; salicylic acid, 5 parts.

XII.—Preservative Salt: Potassium nitrate, 70 parts; sodium bicarbonate, 15 parts; sodium chloride, 15 parts.

XIII.—Another Corning Salt: Potassium nitrate, 50 parts; sodium chloride, 20 parts; powdered boracic acid, 20 parts; sugar, 10 parts.

XIV.—Maciline (offered as condiment and binding agent for sausages): A mixture of wheat flour and potato flour dyed intensely yellow with an azo dyestuff and impregnated with oil of mace.

XV.— Borax 80 parts
Boric acid 17 parts
Sodium chloride  3 parts
Reduce the ingredients to a powder and mix thoroughly.
XVI.— Sodium sulphite, powdered 80 parts
Sodium sulphate, powdered 20 parts
XVII.— Sodium chloride 80 parts
Borax  8 parts
Potassium nitrate 12 parts
Reduce to a powder and mix.
XVIII.— Sodium nitrate 50 parts
Salicylic acid  5 parts
Boric acid 45 parts
XIX.— Potassium nitrate 70 parts
Sodium bicarbonate 15 parts
Sodium chloride 15 parts
XX.— Potassium nitrate 50 parts
Sodium chloride 20 parts
Boric acid 20 parts
Sugar 10 parts
A German Method Of Preserving Meat.
—Entire unboweled cattle or large, suitably severed pieces are sprinkled with acetic acid and then packed and transported in sawdust impregnated with cooking salt and sterilized.
Extract Of Meat Containing Albumen.
—In the ordinary production of meat extract, the albumen is more or less lost, partly through precipitation by the acids or the acid salts of the meat extract, partly through salting out by the salts of the extract, and partly by coagulation at a higher temperature. A subsequent addition of albumen is impracticable because the albumen is likewise precipitated, insolubly, by the acids and salts contained in the extract. This precipitation can be prevented, according to a French patent, by neutralizing the extract before mixing with albumen, by the aid of sodium bicarbonate. The drying of the mixture is accomplished in a carbonic acid atmosphere. The preparation dissolves in cold or hot water into a white, milky liquid and exhibits the smell and taste of meat extract, if the albumen added was tasteless. The taste which the extract loses by the neutralization returns in its original strength after the mixture with albumen. In this manner a meat preparation is obtained which contains larger quantities of albumen and is more nutritious and palatable than other preparations.

FOOT-POWDERS AND SOLUTIONS

The following foot-powders have been recommended as dusting powders:

I.— Boric acid  2 ounces
Zinc oleate  1 ounce
Talcum  3 ounces
II.— Oleate of zinc (powdered)    1/2 ounce
Boric acid  1 ounce
French chalk  5 ounces
Starch  1 1/2 ounces
III.— Dried alum  1 drachm
Salicylic acid    1/2 drachm
Wheat starch  4 drachms
Powdered talc  1 1/2 ounces
IV.— Formaldehyde solution  1 part
Thymol    1/10 part
Zinc oxide 35 parts
Powdered starch 65 parts
V.— Salicylic acid  7 drachms
Boric acid  2 ounces, 440 grains
Talcum 38 ounces
Slippery elm bark  1 ounce
Orris root  1 ounce
VI.— Talc 12 ounces
Boric acid 10 ounces
Zinc oleate  1 ounce
Salicylic acid  1 ounce
Oil of eucalyptus  2 drachms
VII.— Salicylic acid  7 drachms
Boric acid  3 ounces
Talcum 38 ounces
Slippery elm, powdered  1 ounce
Orris, powdered  1 ounce

Salicylated Talcum.—

I.— Salicylic acid  1 drachm
Talcum  6 ounces
Lycopodium  6 drachms
Starch  3 ounces
Zinc oxide  1 ounce
Perfume, quantity sufficient.
II.— Tannoform  1 drachm
Talcum  2 drachms
Lycopodium 30 grains

Use as a dusting powder.

Solutions For Perspiring Feet.—

I.— Balsam Peru 15 minims
Formic acid  1 drachm
Chloral hydrate  1 drachm
Alcohol to make 3 ounces.
Apply by means of absorbent cotton.
II.— Boric acid 15 grains
Sodium borate  6 drachms
Salicylic acid  6 drachms
Glycerine  1 1/2 ounces
Alcohol to make 3 ounces.

For local application.

FOOTSORES ON CATTLE: See Veterinary Formulas.

FORMALDEHYDE:

See also Disinfectants, Foods, and Milk.

Commercial Formaldehyde.

—This extremely poisonous preservative is obtained by passing the vapors of wood spirit, in the presence of air, over copper heated to redness. The essential parts of the apparatus employed are a metal chamber into which a feed-tube enters, and from which 4 parallel copper tubes or oxidizers discharge by a common exit tube. This chamber is fitted with inspection apertures, through which the course of the process may be watched and controlled. The wood spirit, stored in a reservoir, falls into a mixer where it is volatilized and intimately mixed with air from a chamber which is connected with a force pump. The gases after traversing the oxidizer are led into a condensing coil, and the crude formaldehyde is discharged into the receiver beneath.

The small amount of uncondensed gas is then led through a series of two washers. The “formol” thus obtained is a mixture of water, methyl alcohol, and 30 to 40 per cent of formaldehyde. It is rectified in a still, by which the free methyl alcohol is removed and pure formol obtained, containing 40 per cent of formaldehyde, chiefly in the form of the acetal. Rectification must not be pushed too far, otherwise the formaldehyde may become polymerized into trioxmethylene. When once oxidation starts, the heat generated is sufficient to keep the oxidizers red hot, so that the process works practically automatically.

Determination Of The Presence Of Formaldehyde In Solutions.

—Lemme makes use, for this purpose, of the fact that formaldehyde, in neutral solutions of sodium sulphite, forms normal bisulphite salts, setting free a corresponding quantity of sodium hydrate, that may be titrated with sulphuric acid and phenolphthalein. The sodium sulphite solution has an alkaline reaction toward phenolphthalein, and must be exactly neutralized with sodium bisulphite. Then to 100 cubic centimeters of this solution of 250 grams of sodium sulphite (Na2SO3 + 7 H2O) in 750 grams water, add 5 cubic centimeters of the suspected formaldehyde solution. A strong red color is instantly produced. Titrate with normal sulphuric acid until the color disappears. As the exact disappearance of the color is not easily determined, a margin of from 0.1 to 0.2 cubic centimeters may be allowed without the exactness of the reaction being injured, since 1 cubic centimeter of normal acid answers to only 0.03 grams of formaldehyde.

FORMALIN FOR GRAIN SMUT: See Grain. {363}

FRAMES: THEIR PROTECTION FROM FLIES.

Since there is great risk of damaging the gilt when trying to remove flyspecks with spirits of wine, it has been found serviceable to cover gilding with a copal varnish. This hardens and will stand rough treatment, and may be renewed wherever removed.

FRAME CLEANING: See Cleaning Preparations and Methods.

FRAME POLISHES: See Polishes.

FRAMING, PASSE-PARTOUT: See Passe-Partout.

FRECKLE LOTIONS: See Cosmetics.

FREEZING MIXTURES: See also Refrigeration and Refrigerants.

FREEZING PREVENTIVES

Liquid For Cooling Automobile Engines.

—In order to prevent freezing of the jacket water, when the engine is not in operation in cold weather, solutions are used, notably of glycerine and of calcium chloride (CaCl2). The proportions for the former solution are equal parts of water and glycerine, by weight; for the latter, approximately 1/2 gallon of water to 8 pounds of CaCl2, or a saturated solution at 60° F. This solution (CaCl2 + 6 H2O) is then mixed with equal parts of water, gallon for gallon. Many persons complain that CaCl2 corrodes the metal parts, but this warning need do no more than urge the automobilist to use only the chemically pure salt, carefully avoiding the “chloride of lime” (CaOCl2).

A practical manufacturing chemist of wide experience gives this:

A saturated solution of common salt is one of the best things to use. It does not affect the metal of the engine, as many other salts would, and is easily renewed. It will remain fluid down to 0° F., or a little below.

Equal parts of glycerine and water is also good, and has the advantage that it will not crystallize in the chambers, or evaporate readily. It is the most convenient solution to use on this account, and may repay the increased cost over brine, in the comfort of its use. It needs only the occasional addition of a little water to make it last all winter and leave the machinery clean when it is drawn off. With brine an incrustation of salt as the water evaporates is bound to occur which reduces the efficiency of the solution until it is removed. Water frequently must be added to keep the original volume, and to hold the salt in solution. A solution of calcium chloride is less troublesome so far as crystallizing is concerned, but is said to have a tendency to corrode the metals.

Anti-freezing Solution For Automobilists.

—Mix and filter 4 1/2 pounds pure calcium chloride and a gallon of warm water and put the solution in the radiator or tank. Replace evaporation with clean water, and leakage with solution. Pure calcium chloride retails at about 8 cents per pound, or can be procured from any wholesale drug store at 5 cents.

Anti-freezing, Non-corrosive Solution.

—A solution for water-jackets on gas engines that will not freeze at any temperature above 20° below zero (F.) may be made by combining 100 parts of water, by weight, with 75 parts of carbonate potash and 50 parts of glycerine. This solution is non-corrosive and will remain perfectly liquid at all temperatures above its congealing point.

Anti-frost Solution.

—As an excellent remedy against the freezing of shop windows, apply a mixture consisting of 55 parts of glycerine dissolved in 1,000 parts of 62 per cent alcohol, containing, to improve the odor, some oil of amber. As soon as the mixture clarifies, it is rubbed over the inner surface of the glass. This treatment, it is claimed, not only prevents the formation of frost, but also stops sweating.

Protection Of Acetylene Apparatus From Frost.

—Alcohol, glycerine, and calcium chloride have been recommended for the protection of acetylene generators from frost. The employment of calcium chloride, which must not be confounded with chloride of lime, appears preferable in all points of view. A solution of 20 parts of calcium chloride in 80 parts of water congeals only at 5° F. above zero. But as this temperature does not generally penetrate the generators, it will answer to use 10 or 15 parts of the chloride for 100 parts of water, which will almost always be sufficient to avoid congelation. Care must be taken not to use sea salt or other alkaline or metallic salts, which deteriorate the metal of the apparatus.

Frost Bite.

When the skin is as yet unbroken, Hugo Kuhl advises the following: {364}