Materia Medica for Nurses - pocketboek

Purchase of this book includes free trial access to www.million-books.com where you can read more than a million books for free. This is an OCR edition with typos. Excerpt from book: CHAPTER II SYSTEMS OF WEIGHTS AND MEASURES There are two systems of measuring drugs: one is the French or Metric System, the other is the English or Apothecaries' System. The Metric system is the one which is used in all European countries; it has the following advantages: the units are divided into tenths, the units of length, volume and weight are similar, and the units of volume are equal to the units of weight. In this country, the Apothecaries' System is still used, but it is gradually being superseded by the Metric System; and it is simply a question of time when the Apothecaries' System will be abandoned entirely. THE METRIC SYSTEM The elementary unit of measurement in the metric system is the one for length. This is the meter, which is about one ten-millionth part of the distance from the equator to the north pole. It is equal to about 39.37 inches and is written as 1.0m. TABLE OF LENGTH The unit is 1.0 one meter one tenth of the meter " 0.1 one decimeter " " " the decimeter " 0.01 one centimeter " " " the centimeter " 0.001 one millimeter TABLE OF SURFACE A surface one meter long and one meter wide is called a square meter, 1.0 sq. m., which is the unit of surface. This is divided into one hundred square decimeters, each of which is again divided into one hundred square centimeters. Each square centimeter is further subdivided into one hundred square millimeters. TABLE OF VOLUME The volume of a substance is the amount of space which it occupies. A quantity of space one meter long, one meter wide and one meter high, is one cubic meter, which is the unit of volume. This is divided into a thousand cubic decimeters, each of which is again divided into a thousand cubic centimeters and this in turn into a thousand cubic mill...