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CHAPTER XXXVIII.

UNFIT VEGETABLE SUBSTANCES.

(452) Decomposed Vegetables.

No special details need be here given upon the appearances which vegetable substances present when partially or completely decomposed; all persons of ordinary intelligence can distinguish between fresh and stale vegetables. On the other hand, differences of opinion will occur with regard to fruit; if fruit such as apricots, strawberries, gooseberries are but partially decomposed, it is doubtful whether it is fair to seize and destroy them, because the condition is so evident that the public are not defrauded, and bruised and partially mouldy fruit is often sold for making preserve at a low price. Hence in these cases the medical officer must be entirely guided by the extent of the decomposition or condition, and the Author's advice is only to act in those cases of a decided character.

(453) Unhealthy condition of Flour or Bread.

Flour may be simply musty; here again, unless the mustiness is pronounced, it will not be wise to condemn as unfit for food, If it smells only faintly such flour will make fairly eatable bread; on the other hand, flour with evident and strongly smelling mustiness should be unhesitatingly condemned.

(454) Ergot in Flour.

Since ergot causes a special malady, there can be no possible difference of opinion that ergotised flour if discovered should be unhesitatingly condemned. Such flour is dark in colour and has a peculiar odour. Examined by the microscope the little dark masses of ergot may be seen; if also the flour be stained by aniline

blue, all starch granules damaged by ergot, or as for that by any other fungus, will be stained intensely. A portion of the flour may be exhausted by boiling strong alcohol, the alcoholic solution acidified by dilute sulphuric acid and examined by the spectroscope. If the flour is ergotised, the solution will be more or less red and show in dilute solution two absorption bands, one lying in the green near e and a broader and stronger band in the blue between f and g. On mixing the original solution with twice its volume. of water and shaking up with ether or amyl alcohol, or benzine or chloroform, if ergot be present any of these solvents become of a red colour.

(455) Corn Cockle Seeds in Flour.

The

A mixture of these seeds with flour will make the flour unfit for use, the active principle of the Agrostemma or lychnis cithago being saponin, a glucoside with marked irritant properties. The seeds are in shape not unlike a rolled up caterpillar, the surface being beset with little warty projections arranged in rows. surface of the testa, or seed covering, shows, when examined by the microscope, very large thickened cells 1 to 6 mm. diameter, forming on the surface branching tubercles,, beneath which is a loose parenchyma made up of two layers or rows of simple cells; this rests on a thin epithelial membrane composed of flat cells, most of which exhibit a peculiar striation; next to this comes the main substance of the seed, the endosperm, composed of ordinary large-celled parenchyma, filled with very minute starch granules; and lastly, there is the embryo, the structure of which cannot be distinguished from the embryo of other seeds. There are little bodies scattered among the endosperm, consisting of egg or spindleshaped finely granulated grains, from 02 to 1 mm. in long diameter, consisting wholly of saponin, starch, and mucin; these bodies are not peculiar to corn cockle seeds, but occur in other plants of the same natural order-that is, in the clove-worts. F. Beneke has examined the sizes in various plants and gives the maximum as follows spergula 030 mm., beta 057 mm., spinacia 64 mm., agrostemma 122 mm., hence over 07 mm. points to corn cockle. Flour containing corn cockle seeds yields a larger percentage of oil to ether, and the ether extract has an acrid taste and is of a pronounced yellow colour.

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CHAPTER XXXIX.

INSPECTION OF FISH AND MEAT.

(456) Inspection of Fish.

FISH are subject to various parasitic diseases, but the purpose of inspection will be mainly to ascertain whether the fish are stale or fresh. Since a large proportion of both inspectors and medical officers have at one time or another of their lives been amateur fishermen, they will probably know perfectly well the signs of a fresh fish, the bright prominent eye,1 the healthy gills, the peculiar feel of the whole body and the absence of odour when the mouth and gills are opened and the inspector's nose applied close. In a dark place fish beginning to decompose will also here and there shine with a phosphorescence, but before this takes place an odour will nearly always be detected. The slightest taint in fish renders them unfit for use and justifies condemnation.

(457) Inspection of Meat.

Since it is only possible in a minority of cases to tell from a

1 One of the best descriptions of the dodges of fishermen is to be found in Blackmore's novel, The Maid of Sker. "I felt that I could trust nobody to have proper faith, especially when they might behold the eyes of the fish retire a little, as they are apt to do when too many cooks have looked at them. . . . . When the eyes of a fish begin to fail him through long retirement from the water, you may strengthen his mode of regarding the world (and therefore the world's regard for him) by a delicate bit of handling. Keep a ray fish always ready-it does not matter how stale he is-and on the same day on which you are going to sell your bass, or mullet, or cod, or whatever it may be, pull a few sharp spines, as clear as you can, out of this good ray. Then open the mouth of your languid fish and embolden the aspect of either eye by fetching it up from despondency with a skewer of proper length extending from one ball to the other. It is almost sure to drop out in the cooking, and even if it fails to do so none will be the wiser, but take it for a provision of nature-as indeed it ought to be."

look at the muscles or flesh of a slaughtered animal whether it was in good health or the reverse, the medical officer should aim at inspecting the entire carcase.

It does not admit of two opinions that, knowing what we do of the importance of a healthy meat supply, the time has come to insist upon a proper inspection of meat; this proper inspection can only be made if in each town the slaughtering is centralized; it is to be hoped that ultimately such meat inspection will occupy the whole time of one or more pathologists who should have every appliance for the microscopical examination and also for bacteriological research.

A medical officer of health is expected by the law to give a glance at a leg of mutton, or a piece of beef, to detect there and then the seeds of disease and to at once convey it before a magistrate. Hence as this is an impossibility, the work is either not done at all, or the inspection is only made of absolutely putrid pieces of meat, or of cases concerning which special information has been given.

(458) Characteristics of Good Meat.

All fresh meat is acid to test paper; directly decomposition commences the acidity diminishes and then is replaced by an alkaline reaction. If a little meat is chopped up and warm water poured upon it, the odour should not be disagreeable; on the other hand, meat from a diseased animal has a sickly peculiar smell and occasionally it possesses a distinct odour of the medicine which the farrier has drenched the sick animal with. In this way sometimes aloes may be smelled. The colour of the meat should be normal; each animal's meat has a colour of its own, the peculiar pale tint of veal or of mutton, and the deep red of beef are examples; any marked deviation from the colour is a suspicious sign. Calves, sheep, and pigs, being freely bled to death, should the meat of these animals have an abnormal red hue it may be a sign that they were not killed in the usual manner and therefore this will again be suspicious.

Meat which is sodden and contains much water is not unfrequently diseased.

To examine meat practically a knife should be run into it, well

into the centre of the mass, and the knife carefully smelled on withdrawal; if opportunity admits a portion of the suspected meat may be examined by the microscope.

A portion may also be soaked in distilled water and a little litmus added so as to test its reaction.

To detect trichinæ see page 629.

(459) The Detection of Tubercle Bacilli.

To detect tubercle bacilli in meat it will be necessary to very carefully dissect out any little portion which looks suspicious; cut fine sections of it and stain the sections with Gibbes' double stain.

Gibbes' double stain is made by dissolving 2 parts of rosaniline hydrochlorate, 1 of methylene blue, in 3 parts of aniline oil, and 15 parts of rectified alcohol; lastly dilute with 15 parts of water.

The sections are soaked in this solution first made very hot for several hours, the excess of stain is washed away with methylated spirit; the sections are dried and mounted in Canada balsam. The search for tubercle bacilli must be made with a high power and with good illumination.

Muscular tissue may contain the germs of tubercle and yet the most experienced microscopist fail to detect them, but by injecting the flesh juice into guinea-pigs their presence may yet be showne.g. At Munchen some experiments have been made recently by Steinheil1 as to the possibility of infecting guinea-pigs with the products from the muscles of persons affected with phthisis. The material used was portions of the psoas muscles of nine patients who died of phthisis. The muscle was cut up into very fine pieces, and submitted to the pressure of a screw press. The juice obtained was injected into guinea-pigs. Of eighteen guineapigs thus treated fifteen died of tuberculosis, although no tubercle could be detected in the muscles so used. Steinheil draws the conclusion that the muscular flesh in advanced human phthisis is infectious as a rule; hence the possibility that the flesh of animals affected with bovine tuberculosis is dangerous cannot be denied.

1 Munchen med. Wochenschrift, 1889, Nos. 40 and 41.

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