Adulterations of Coffee.-The adulterations of coffee are numerous- chicory, roasted wheat, rye, and potato flours, roasted beans, mangel-wurzel, acorns, burnt sugar, or black jack; and when mixed with adulterated chicory, it may also contain any of the sophistications mentioned under CHICORY. The adulterations are generally to be found in the ground coffee, but the berries are sometimes mixed with chicory compressed into shapes resembling coffee berries. In 1850, Messrs. Duckworth of Liverpool actually took out a patent for this purpose.

The adulteration of coffee was at one time a regular organised industry; and there existed, ten years ago, two manufactories in France-one at Lyons and the other at Havre -expressly established for the purpose of mixing coffee with burnt cereals and the scorched outer covering of cocoa.

Detection of Adulterations.-Chicory is the principal adulteration, and its microscopical character, its sophistications, &c., should be carefully studied. See CHICORY.

The process of ascertaining an admixture of any foreign substance with coffee is tolerably certain.

1. Preliminary Examination.-Strew a little of the powder on the surface of cold water. Genuine coffee floats, and does not colour the water; chicory and burnt sugar rapidly sink to the bottom, and impart a brown colour to the liquid. If any sediment occurs, it will be well to remove it with a pipette for microscopical examination.

2. Microscopical Examination.-This will reveal most of the adulterations of coffee. It is well to obtain an accurate knowledge of the structure of pure coffee and pure chicory first. (See CHICORY.) If a sample of coffee be moistened with water, and small black shining particles be seen in the field, surrounded by a dark coloration, burnt sugar is present.

3. By making standard infusions of pure coffee and chicory, and then taking the same weight of the suspected coffee, and comparing the colour, it is possible to obtain a very accurate idea of the quantity of chicory added.

Leebody recommends this to be done as follows: Take 1 gramme of the unknown mixture, and 1 gramme of a standard mixture of equal parts of chicory and coffee; remove all the colouring matter from each sample, and make the extract of each up to the same bulk. Put 50 c. c. of the filtered extract from the unknown mixture in a Nessler cylinder, and determine by trial how many c.c. of the extract from the standard

water to make up the 50 c.c., will give the same colour. In calculating the percentage of chicory present, closely accurate results are obtained in practice by assuming the tinctorial power of chicory to be three times that of coffee. (J. R. LEEBODY, Chemical News, xxx. 243.)

It results from this, that coffee adulterated with chicory will give an ash containing silica, with less carbonic acid than normal, more iron and more chlorine, all of which can be easily determined.

8. The proportion between the soluble and insoluble constituents of the ash in water appears constant. On this account,'Mr. Allen proposes it in union with other tests as a valuable indication. He says

"I ignited three samples of genuine coffee of different kinds and three of chicory, taking 5 grammes for each experiment. After weighing, the ash was boiled in water, the liquid filtered, the clear solution evaporated to dryness, and the residue heated to full redness and weighed. The following were the proportions in 100 of the sample :

Average of chicories 5:06 1.74 == 34

"The proportion the soluble ash of the chicories bears to the total varies considerably, owing to the different quantities of silica present in the samples, and the percentage of soluble ash is not so constant as in the case of coffee.

**Assuming 3.24 per cent. as the average soluble ash of coffee, and 174 as that of chicory, the percentage of coffee in a mixture would be represented by the following equation, where C is the percentage of coffee and S the percentage of soluble ash.

autumnale). It was formerly supposed to be identical with veratria. It differs from veratria in being more soluble in water, and not exciting sneezing. It is extremely poisonous. Sulphuric acid turns it of a yellowish brown. Nitric acid turns it violet, passing into indigo blue, green, and yellow.

Collector of Rates - See OFFICERS, APPOINTMENT OF.

Colostrum, or "Beastings "-The first milk yielded by the cow after parturition. It is of a somewhat viscid or stringy consistence, with a turbid and yellowish appearance, and a strongly alkaline reaction. For the first ten days after the cow has calved, it is totally unfit for use. It contains more albumen than caseine, and hence undergoes coagulation on boiling. Under the microscope a number of large irregular bodies are seen, which consist of conglomerations of small fat globules, held together by an amorphous, somewhat granular substance. These are called colostrum corpuscles.

Colostrum has a somewhat sickly odour and a purgative action.

Colouring Matters-The following list gives the names of the principal substances used for colouring food, drugs, &c.:—

Combustion, Products of-It is found that coal of average quality gives off in combustion

1. Carbon. About 1 per cent. of the coal is given off as fine carbon, and tarry particles. 2. Carbonic Acid.

3. Carbonic Oxide.-When there is abundance of air given to fuel at the proper time

collected on Pouchet's aeroscope, when only a very small quantity of air is drawn through. It would appear that it is chiefly from combustion that the air of towns contains so much acid as to make the rain-water acid.

Augus Smith found in Manchester, in 1868, the rain to contain from 5'6 grains to 14 grain of sulphuric acid (free and combined), and from 1-277 to 0278 grains of hydrochloric acid, per gallon. The sulphuric acid is always larger in amount than the hydrochloric. Coal gas has the following composition:Hydrogen to 45.58

40

Marsh gas (light carburetted? 35 hydrogen)

Carbonic oxide

3

to

As much as 11 per cent. of carbonic oxide, 56 per cent. of the light carburetted hydrogen, and 60 grains of sulphur have been found. The Parliamentary maximum of sulphur is 20 grains in 100 cubic feet.

When the gas is partly burnt, the hydrogen and light and heavy carburetted hydrogens are almost destroyed, nitrogen (67 per cent.), water (16 per cent.), carbonic acid (7 per cent.), and carbonic oxide (5 to 6 per cent.) being the principal resultants which escape generally into the air of rooms. If the combustion were perfect, there would be little carbonic oxide.

One cubic foot of gas will destroy the entire oxygen of about 8 cubic feet of air, and it will raise the temperature of 31-290 cubic feet of air 1° F. Weaver found as much as 532 volumes of carbonic acid per 1000 in the room of a framework-knitter in Leicester, with fourteen gaslights burning. In other workrooms the amounts were 528, 46, down to 2:11 volumes per 1000. Such large amounts are undoubtedly very injurious.

Wood produces carbonic acid, acetic acid, and water, but few compounds of sulphur. 1 lb. of dried wood demands about 120 cubic feet of air for complete combustion.

combustion. Dr. Zock says that oil, for an equal illuminating power, gives off less carbonic acid than gas. Dr. Olding found that candles, for an equal illuminating power, contaminated the air more than gas; the latter, though, gives out more water.

Tobacco smoke contains particles of nicotine* or its salts, and probably of picoline bases. There are also much carbonic acid, butyric acid, and ammonia.

Committees-A committee for sanitary purposes is often a better body for the despatch of business than a larger board.

Boards of guardians for unions of any size have generally so much business to transact at their ordinary meetings, that when they form a sanitary authority, it is generally at a late hour, and the sanitary business necessarily gets hurried through or slurred over, so that it is well for those thus situated to delegate all their powers to a committee, who should meet on some other day than a board-day.

In those districts which are formed of several unions which have united in order to secure the services of one health officer, a central committee, composed of delegates from each of the local authorities, if not absolutely essential, would be found of great utility. Such a committee could meet at least once a year. See DISTRICTS, UNITED.

"A rural authority may, at any meeting specially convened for the purpose, delegate for the current year of their office all their powers to a committee consisting wholly of their own members; provided that one-third at least of such committee shall consist of exofficio guardians, but in case an adequate number of such ex-officio guardians does not exist, then the number deficient shall be made up of elected guardians; and any such committee shall have the powers by this Act vested in the rural authority by which it was formed, and shall be deemed to be during such year of office as aforesaid the rural authority of the district."-(P. H., s. 201.)

"Every urban authority may from time to time appoint out of their own number so many persons as they may think fit, for any purposes of the Public Health Act, which in the opinion of such authority would be better regulated and managed by means of a com

Oil.-A lamp with a moderately good wick will burn about 154 grains of oil per hour, and will consume the oxygen of about 3-2 cubic feet of air, and produce about a cubic foot of carbonic acid. 1 lb. of oil demands from 140 to 150 cubic feet of air for complete

pointed shall in no case be authorised to borrow any money, to make any rate, or to enter into any contract, and shall be subject to any regulations and restrictions which may be imposed by the authority that formed it." (P. H., s. 200.)

*This is denied. See TOBACCO.

Committees, Parochial.-Parochial committees, according to their constitution, are either an assistance or an obstruction to sanitary work.

The best men to be on a parochial committee, speaking generally, are (1) the guardians of the parish; (2) the ex-officio guardians; (3) the clergyman of the parish; (4) one or two of the principal owners of property in the parish. "A rural authority (including any committee so formed as aforesaid) may, at any meeting specially convened for the purpose, form for any contributory place within their district a parochial committee consisting wholly of members of such authority or committee, or partly of such members and partly of such other persons liable to contribute to the rate levied for the relief of the poor in such contributory place, and qualified in such other manner (if any) as the authority forming such parochial committee may determine.

"A rural authority (including any committee so formed as aforesaid) may from time to time add to or diminish the number of the members, or otherwise alter the constitution of any parochial committee formed by it, or dissolve any parochial committee.

"A parochial committee shall be subject to any regulations and restrictions which may be imposed by the authority which formed it: provided that no jurisdiction shall be given to a parochial committee beyond the limits of the contributory place for which it is formed, and that no powers shall be delegated to a parochial committee except powers which the rural authority could exercise within such contributory place.

"A parochial committee shall be deemed to be the agents of the authority which formed it, and the appointment of such committee shall not relieve that authority from any obligation imposed on it by Act of Parliament or otherwise.

66

A parochial committee may be empowered by the authority which formed it to incur expenses to an amount not exceeding such amount as may be prescribed by such authority; it shall report its expenditure to such authority as and when directed by such authority, and the amount so reported, if legally incurred, shall be discharged by such authority."-(P. H., s. 202.)

Any casual vacancy occurring by death, resignation, disqualification, or otherwise, in any committee, may be filled up within one month, by the authority which formed such committee, out of qualified persons."-(P. H., s. 203.)

The following duties may, in the opinion of the Local Government Board, be assigned to parochial committees :

1. To inspect their district from time to time, with a view of ascertaining whether any works of construction are required, or any nuisances exist which should be abated.

2. To superintend the execution and maintenance of any works which may be required, or have been provided for the special use of the district; and to give directions for any repairs or other matters requiring im mediate attention in relation to such works, which fall within the reasonable scope of the authority which they possess as agents of the sanitary authority.

3. To consider complaints of any nuisances, and the action of the medical officer of health or inspector of nuisances thereon; and to inform these officers of any nuisances requiring their attention, and to give such directions for abatement of the same, in cases of urgency, as the circumstances may seem to require.

4. To examine and certify all accounts relating to expenditure chargeable as special expenses within their district.

5. To report to the sanitary authority from time to time the several matters requiring their attention, and the manner in which their officers and servants have discharged their duties.

The proceedings of a committee are to be conducted in strict accordance with the rules given in the first schedule of the Public Health Act, 1875, as follows:

Rules applicable to Committees of Local Authorities, other than Councils of Boroughs, and to Joint Boards.

1. A committee or joint board may meet and adjourn as it thinks proper.

2. The quorum of a committee or joint board shall consist of such number of members as may be prescribed by the authority that appointed the committee or joint board, or, if no number is prescribed, of three members.

3. A committee or joint board may appoint a chair

man of its meetings.

4. If no chairman is elected, or if the chairman elected is not present at the time appointed for holding any meeting, the members present shall

choose one of their number to be chairman of such meeting.

5. Every question at a meeting shall be determined by a majority of votes of the members present and voting on that question.

6. In case of an equal division of votes, the chairman shall have a second or casting vote.

7. The proceedings of a committee or joint board shall not be invalidated by reason of any vacancy or vacancies amongst their members, or any defect in the mode of appointment of such committee or joint board, or of any member thereof.

8. Any minute made of proceedings at a meeting, and copies of any orders made or resolutions passed at a meeting, purporting to be signed by the chairman of the meeting at which such proceedings took