:.Iarcli29, 1373.] 
THE PHARMACEUTICAL JOURNAL AND TRANSACTIONS. 
765 
tionable bodies can only be identified by the chemist and 
microscopist; but it is often possible by very simple means 
to ascertain whether or not a particular article is impure 
nr adulterated—whether it exhibits the characters that 
serve to distinguish the substance, though it is not possible 
to name the particular impurity or adulterant without the 
possession of that “ competent medical, chemical, and mi- 
•eroscopical knowledge” required by the Adulteration Act. 
Information of the first kind should be possessed by every 
medical man, and even by the head of every household, 
and the lecturer’s aim was to afford as much of this class 
of information as happens to be available at present. The 
ohief subject-matter of the lecture is condensed in the 
following short notes ; but mention is therein made only 
•of the more important articles of food, excluding most of 
the so-called condimental foods on one hand, and alcoholic 
liquids on the other. 
Potable Water. —Its impurities are mineral (lime and 
magnesia compounds, iron, sulphuretted hydrogen, etc.), 
and organic “sewage contamination/’ including animal 
and vegetable nitrogenous matter, either capable of, or in 
process of decomposition, and the products of such change). 
Good water should be free from colour, unpleasant odour 
and taste, and should quickly afford a good lather with a 
small proportion of soap. If half a pint of the water be 
placed in a perfectly clean, colourless, glass-stoppered 
bottle, a few grains of the best white lump sugar added, 
and the bottle freely exposed to the daylight in the window 
of a warm room, the liquid should not become turbid, 
even after exposure for a week or ten days. If the water 
become turbid, it is open to grave suspicion of sewage con¬ 
tamination ; but if it remain clear, it is almost certainly 
safe. We owe to Heisch this simple, valuable, but hitherto 
strangely neglected test. Frankland has shown that it is 
•extremely delicate, and that the production of turbidity 
under the circumstances named is due to the minute quan¬ 
tity of phosphoric acid present in sewage.* The Vartry 
water, as delivered from the street mains in Dublin at 
present, withstands this test perfectly; but it often be¬ 
comes very impure when allowed to pass through ill-kept 
cisterns. 
Tea. — Adulterations. There are two chief classes of 
teas—the green and black varieties. Under the first head 
are included the Hysons, Twankay, and Gunpowder; and 
under black teas, Pekoe, Souchong, Congou, and Bohea. 
Both classes are subject to many serious adulterations at 
the hands of the exporters, and again on arrival in Europe. 
Mixtures of different kinds of tea are legitimately made 
in the course of trade for the purpose of suiting special 
tastes; but inferior varieties are often dishonestly mixed 
with the more costly kinds in order to increase profits. 
Leaving aside the consideration of “tea-mixing,” we find 
that to green and black teas have often been added the 
leaves of other plants. Those of plum, sloe, ash, willow, 
poplar, hawthorn, beech, plane, orange, elm, horse-chestnut, 
elder, and oak have been detected. These leaves are dried 
and prepared by roasting and “facing” so as to resemble 
genuine tea very closely. The product is sometimes called 
“Maloo mixture.” Facing is used for the purpose of 
colouring the leaves and increasing weight. The bodies 
employed are china clay, gypsum, chalk, French chalk, 
black lead, Prussian blue, indigo, chromate of lead, carbo¬ 
nate, and even arsenite of copper, Venetian red, and fine 
white sand. The powders are attached to the leaf-sui’face 
by a convenient adhesive material. Spent (exhausted) tea- 
leaves are often dried, coloured with catechu and an iron 
salt, then faced, and the product mixed with good tea, 
“ Maloo mixture,” or Lie tea. The last-named substance 
is made up of the tea and other leaves, sand, or plaster of 
Paris, bound together by starch or gum, so as to form 
granular particles that can be “ faced,” so as to resemble 
black or green gunpowder. Genuine Tea , when placed in 
a muslin bag and kneaded in warm water for a few mi¬ 
* The turbidity is caused by fungoid growths. 
nute3 should not give up any powder, quickly subsiding 
when the water is allowed to stand. 
Coffee.—A dulterations. Chicory, acorns, sawdust, roasted 
roots of various kinds, and grain, tan, Croats, lentil seeds, 
baked livers, Venetian red, burnt sugar. Admixture with 
chicory is allowable if the compound be truly labelled. 
Genuine Coffee should not cake when pinched between the 
fingers. When a little is thrown on cold water it floats, 
and very slightly tinges the water. Adulterated coffee 
sinks, and rapidly colours the water brown. 
Cocoa. — Adulterations. Chicory, cocoa-husk, fats, 
starches, sugar, Venetian red, bole. Genuine Cocoa should 
not have a sweet taste, nor red colour. As much cocoa as 
can be piled up on a threepenny piece, when placed on a 
square of platinum foil, and strongly heated by a spirit- 
lamp flame should burn almost completely away, leaving 
a very minute quantity of reddish coloured ash.* The 
same remarks apply to chocolate. 
Sugar.—Adulterations and Impurities. Fine white loaf- 
sugar is rarely adulterated, but coloured sugars sometimes 
contain chalk, sand, clay, starch, sugar, flour, dextrine, 
plaster of Paris: as impurities, fragments of cane, mo¬ 
lasses, vegetable albumen, and sugar-mites or acari. Good 
Sugar should be free from the least bitter taste, and ought 
to dissolve completely in water. Loaf-sugar should give a 
perfectly clear and colourless solution; brown sugar, a 
clear but coloured liquid. If insects be present they float 
on the syrup, and appear as small specks, which can be 
easily removed for microscopic examination. Bon-bons, 
unless when mixed with harmless starch or injurious white 
or coloured mineral powders, produce clear solutions when 
dissolved in water. If any insoluble residue be left, the 
deposit should be allowed to settle, the liquid poured care¬ 
fully off, and the powder collected, dried, and heated on 
platinum-foil. If white, and wholly combustible, it pro¬ 
bably consists of starch. Chromate of lead (yellow), 
arsenite of copper (green), china clay and gypsum (white), 
and most other injurious mineral pigments, give insoluble 
and fixed powders. Sulphide of mercury or vermilion, 
though volatile when heated on platinum-foil, is easily re¬ 
cognised by affording a heavy red powder on treatment of 
the sweets with w r ater. 
Milk. — Adulterations. The chief is undoubtedly water; 
but skim-milk, annatto, brains, chalk, gum tragacanth, 
and other gums; sugar, decoction of white carrots, starch, 
and turmeric, are stated to be used occasionally. Good 
Milk should be free from acidity, and when allowed to 
stand in a vessel ought not to deposit solid matter. When 
placed in a tall graduated glass cylinder, it should throw 
up at least 10 per cent, of cream after standing for twelve 
hours. This is on the whole the least objectionable rough 
test that can be used. 
Butter. — Adulterations. Water, much salt, starch, flour, 
dripping, and lard. Good Butter should not have a rancid 
smell. When a quantity is melted and poured into a 
small narrow phial, and the latter allowed to stand near 
to a good fire, the milky layer of water that falls to the 
bottom of th e bottle should not form more than one-tenth 
of the tota\ bulk of fluid. When the melted butter is 
poured off, the water should not strike a blue colour when 
shaken with a drop of tincture of iodine. 
Bread. — Adulterants. Water, rice, potato, and other 
stax*ches, salt, alum, bone-dust, clay, carbonate of magne¬ 
sium, chalk, gypsum, and sulphate of copper; or impure 
from bad flour. Good Bread is sweet and agreeable to the 
taste. It does not present a mouldy appearance, and ought 
not to give a thick liquid when steeped in water. If bread 
become soft and sodden on standing, it is probably adul¬ 
terated with rice. When a piece containing much alum 
is dipped in a very weak solution of the colouring matter 
of logwood, the bread is quickly dyed of a purple tint. 
* The microscope is alone able to detect mixtures of 
many organic bodies, a3 starches, fat3, chicory, etc., in this 
and other cases. The simple tests given usually servo 
simply to exclude injurious substances. 
