MECHANICS REQUIRED FOR THE ADDITIONAL SUBJECTS FOR HONOURS AT THE PREVIOUS EXAMINATION AND FOR THE ORDINARY DEGREE. BY J. MCDOWELL, M.A., F.R.A.S., PEMBROKE COLLEGE, CAMBRIDGE. CAMBRIDGE: DEIGHTON, BELL, AND CO. LONDON: BELL AND DALDY. 1867. neciass 10-31-39 ови PREFACE. THE present work is one of a series intended for the Previous Examination and the Ordinary Degree, according to the new scheme which came into operation last December. I have endeavoured to make the definitions and investigations clear, precise, and accurate; and to present them in a convenient form for writing out at an examination. In Article 15 I have given a proof of the first part of the Parallelogram of Forces, which, by its brevity and simplicity, will, I trust, free Duchayla's proof from the reproach of being "long and difficult.” In Article 44 the conditions of equilibrium of a rigid body acted on by any number of forces in the same plane are deduced without the aid of analysis. I have not found these conditions satisfactorily deduced in any elementary work without the aid of analysis or the composition of couples. Trigonometrical methods have been very sparingly introduced, and wherever they occur, the Article or Section has been marked with an asterisk. Though there is nothing in the work which may not fairly be set from time to time at the Previous or Degree Examination, yet as all students do not require to read exactly the |