Applied medical chemistry : a manual for students and practitioners of medicine / by Lawrence Wolff.

  • Wolff Lawrence.
Date:
1885
Catalogue details

Licence: Public Domain Mark

Credit: Applied medical chemistry : a manual for students and practitioners of medicine / by Lawrence Wolff. Source: Wellcome Collection.

Provider: This material has been provided by the Royal College of Physicians of Edinburgh. The original may be consulted at the Royal College of Physicians of Edinburgh.

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    APPLIED MEDICAL CHEMISTRY. PART I. APPARATUS AND MANIPULATIONS. The execution of chemical manipulations depends on the employment of certain apparatus, which may be considered under the head of physical and technical. PHYSICAL APPARATUS. Physical apparatus comprises the instruments of precision needed to determine the influence of physical force upon matter. As this is relative in its nature, standards have been adopted by which to determine it. Gravity influences bodies by attraction in proportion to their amount. The attraction exerted upon bodies by the earth, manifested by the arrest of their progress towards its centre, has been termed their weight. This is ascertained by scales or balances, which in their execution involve different mechanical principles, to overcome friction, etc. The weights employed, almost universally, in chemical manipulations are those of the so-called metric sys- tem, depending for its unit on the metre, the ten-millionth part of the quadrant of the earth. The metre is equal to io decimetres, ioo centimetres, or 1000 millimetres. The litre, the unit of fluid measure, is the cube of one decimetre, equal to iooo cubic centimetres (c.c.). The unit of weight is the gramme (grm.) the one one-thousandth part of a litre of pure water at its maximum density. One gramme is equal to 10 decigrammes, or ioo centigrammes, or iooo milligrammes. Thus one cubic centimetre (c.c.) of water at its maximum den- sity is equal to one gramme in weight. As the weights in or-