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1,728 cubic inches 1 cubic 1 stere = 1 cubic metre.

27 cubic feet

foot. = 1 cubic yard.

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The Committee of the Privy Council on Education in a Memorandum (Mem. 5) issued in August 1893, to their Inspectors on Examination in the metric system, remark that the education code provides that scholars in the fifth and higher standards shall be examined in the principles of the metric system, i.e., on the convenience of adopting systems of coinage and of weights and measures in which the increase of values or of quantities proceeds by multiples of ten, and their diminution by tenths. So long as these

principles are grasped, it is immaterial whether instruction in the system is illustrated by the metre, with its subdivisions and multiples, or by some other unit; but it will probably be found most convenient to illustrate them by reference to the metre and the franc. The metre can be readily compared with the yard, and its approximate length can be readily remembered, if it is taught in the form of 3 feet 3 inches, in which the number three alone is employed. No other calculation should be required than small addition sums, showing that every complete ten of a lower denomination forms a complete unit of the next higher denomination; e.g.—

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One school inspector in his report suggested that "School managers would do well to adopt an old suggestion, and provide their schools with such of the standard weights and measures as they conveniently can; a few "hours weighing and measuring would make the children more at home with them than many hours of bare "learning the tables", and some School Boards now provide educational models of weights and measures; such as those designed by Mr. F. W. Levander, F.R.A.S., and Mr. G. Evans.

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PART VI.

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15.-WEIGHTS AND MEASURES USED FOR
SPECIAL PURPOSES.

ceutical or apothe

weights

The weights and measures used by pharmacists, or Pharmachemists and druggists, are regulated for the purposes of trade by the Weights and Measures Act, 1878, s. 20, which caries' provides that "Drugs, when sold retail, may be sold by and apothecaries' weight." For dispensing purposes, the measures. Medical Act, 1858, section 54, provides that the General Council of Medical Education and Registration of the United Kingdom "shall cause to be published, under their direction, a book containing a list of medicines and compounds, together with the true weights and measures of which they are to be mixed." This published book is known as the "British Pharmacopoeia," which by the Act 25 and 26 Vict. c. 91. (1862) superseded the Pharmacopoeias hitherto in use in England, Scotland, and Ireland. In the British Pharmacopoeia of 1885, the edition still in use, both Imperial and Metric weights and measures are used, Imperial measures only in the body of the book, and the alternative use of metric weights and measures is extended to analysis, whether gravimetric or volumetric. In the new forthcoming edition of the Pharmacopoeia it is understood that this arrangement will be modified by a more extensive application of the metric system, The avoirdupois ounce

and pound are the weights practically used in the sale of medicines :

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Relation of Measures to Weights.

1 minim (m.) is the measure of 0·91 grain weight of water.

1 fluid drachm (f. 3)

1 fluid ounce (f. 3)

1 pint (O.)

1 gallon

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Apothecaries' (Old) Weight.

20 grains (gr.)

3 scruples, or 60 grains

8 drachms, or 480 grains 12 ounces, or 5,760 grains

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= 1 scruple,

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lb.

= 1 ounce, = 1 pound, The scruple and drachm, although not introduced into the Pharmacopoeia of 1885, are still used in prescriptions.

The Fahrenheit scale of temperature is followed ard specific gravities are referred to a standard temperature of 60° F. The Pharmacopoeia recognises that graduated glass measures of Imperial denominations should be graduated at the legal temperature of 62°, the common practice with chemists, but, with regard to volumetric vessels and specific gravity bottles, these have to be marked at 60° F., a temperature also commonly recognised by chemists for

volumetric purposes. If, therefore, volumetric measures are used graduated at 60° in conjunction with Imperial measures, the determination would require a slight correction if exact results are to be obtained.

The several denominations of apothecaries' weights and measures legal for use in trade are given in Appendix No. 1; such denominations were legalised by H.M.'s Order in Council, dated 14 August 1879. The Annual Calendar of the Pharmaceutical Society of London gives also a list of all the Imperial and Metric weights and measures used in pharmacy.

According to Hoblyn (" Dictionary of Medical Terms ") the Edinburgh and Dublin Colleges formerly retained the old signs for the capacity measures-for the gallon cong. (Roman Congius); for the pint lb.; the ounce 3; the drachm 3; scruple 9, and the drop gt. (French goutte). Dr. Ch. R. C. Tichborne acquaints the writer that these old signs also are still in use in prescription writing, particularly the last four.

The following weights and liquid measures were set forth in the Pharmacopoeia Collegii Regalis Medicorum, Londinensis, 1851, as those then authorised to be used by apothecaries :

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