Domestic Science

Preface in Part II. Special attention has been paid to those portions of the subject which experience has shown are usually imperfectly grasped perhaps on account of the difficulty of providing the student with ready examples of domestic application and the theoretical side of the subject, e.g. the ideas o energy and of molecular action, is treated more fully than is usual in works of similar character. Parts I and II will provide sufficient material for a course of at least two years for pupils in secondary schools, and will be found to cover the requirements of many examinations, such as the Oxford Senior Local and those held under the auspices of the Board of Education at the various Domestic Training Centres. The authors thanks are due to Messrs J. and A. Churchill for permission to reproduce Figs. 20, 27, 79, and 95, and to Messrs Macmillan and Co. for Figs. 21 and 87. For many suggestions, valuable criticisms and useful received from the General Editor of the series while the book was in the press, the writer tenders his grateful thanks. CHELSEA, March, 1915. CHARLES W. HALE. NOTE. The London County Council accepts no responsibility for the authors opinions and conclusions. CONTENTS ANSWERS to Questions involving calculations 317 INDEX 319 LIST OP ILLUSTRATIONS FIG. PAGE 1. Scale showing inches and centimetres . . 5 2. Measurement of length with scale of inches . 6 3. Method of graduation and cross section of scale . 9 4 Measurement of curved lines . . . 14 5. Inside and outside calipers ... . . ..... 17 6. Method of using simple vernier . . . 19 7. Comparison of square foot and square decimetre 22 8. Areas of simple rectilinear figures . . ... 26 9. Area of irregular figure byuse of squared paper 29 10. Relation of area of circle to square of radius ... 32 11. Comparison of cubic inch with cubic centimetre 34 12. Volume of rectangular parallelepiped, . 35 13. Volume of rectangular slab . . . 36 14. Triangular and . . . hexagonal prisms 37 15. Right circular cylinder .... . . 37 16. Graduated vessels for measurement of capacity 38 17. Method of reading graduated vessels . . 40 18. Spring-balance . . . . . . 46 19. Apparatus for illustration of Principle of Moments 48 20. Simple r chemical balance Y . . . - 51 21. Method of holding pipette . . . . -. 58 22. Method of using burette . . . . 59 23. Steelyard . . . . . . . 60 24. Density flasks . . ., . . 67 25. Apparatus for determination of fluid pressure at different depths in a liquid ., - . 84 FIG. List of Illustrations ix 26. Simple hydraulic press . ., V . V PAGE 87 27. Method of weighing a solid in a liquid . . 89 28. Hydrometer ..., . - . 29. Apparatus for illustrating variations of barometric 30. Siphon pressure . S . . -. ... . ., if barometer . . . V 99 31. Apparatus for demonstrating Boyles Law . 102 32. Centre of gravity of a plane figure . . .109 33. Positions of varying stability of a thin lath . 92 97 112 34. Expansion of a bar of metal . - . . . 124 35. Gravesandes ball and ring . . 36. Unequal expansions of different liquids . . 127, . . 126 37. Expansion of a gas . . . v . 128 38. S and X pieces for strengthening brickwork . 132 39. Method of softening capillary tubing . . 137 40. First stage in making thermometer . . 138 41. Method of filling thermometer . . . 139 42...