Many of our readers will be anxious to carry their microscopic investigations to a more advanced stage than we have reached in our pages. Some will have the advantage of a teacher, and it is a great advantage to have someone who can show rather than merely explain what should be done; others not so well placed may like to know a few really useful books which will help them in their work. “The Microscope and its Revelations,” by B. H. Dallinger, is a large and therefore costly work, but it contains a rare fund of information for the microscopist. Smaller and eminently suitable for the general worker is “Modern Microscopy,” by Messrs Cross & Cole. Those who wish to specialize in one of the sciences, such as Botany, Zoology, or Geology, will find no lack of books dealing with the subject that most appeals to them. For photographers who are also microscopists, we know of no better books than “Practical Principles of Plain Photomicrography,” by G. West, or the more advanced “Handbook of Photomicrography,” by Messrs Hind & Randles. Neither books nor teacher will be able to reveal to any of us all the secrets of the microscope. By its means a new world is unfolded before the eyes of mankind, a world of unlimited possibilities. No man will ever see all that the microscope can show him, each day some fresh wonder is looked upon for the first time. As a hobby, microscopy can hardly be excelled. It is a sensible hobby and, after the initial outlay, need cost us but a few pence each year. We hear someone say that he prefers an outdoor hobby, but surely the microscope, if used intelligently, will take us out of doors. The search for specimens is one of the attractions of microscopy. As an instrument for the serious worker the microscope compares favourably with any other invention of mankind. Think for a moment what we owe to the microscope in a hundred and one walks of life, and then you will realize the romance attached to the instrument, and its revelations from the days of Euclid to the present time. INDEX Abbe, 285. Aberration, chromatic, 47. Aberration, spherical, 49. Aconite, 259. _Actinophrys Sol_, 75. Adjustment, coarse, 58; fine, 59. Adulteration of food, 137. _Algæ_, 225. Alkaloids, 144. American water-weed, 98. _Amœba Proteus_, 67. _Anatome Plantarum_, 32. Animal cells, 168. Animalcule, bell, 70; protean, 67; slipper, 68; sun, 75; wheel, 74. Animal fibres, 262. Annealing, 284, 289. Aphids, 36. Apparatus, choice of, 137. Aristotle, 32. Bacilli, 159. _Bacillus Subtilis_, 160. Bacteria, 36, 37, 38, 152; cultures of, 165; examination of, 160; origin of, 155; size of, 156; splitting of, 157; staining of, 162. Barnacle, 221. Bees, 34, 195, 199. Bird’s head, 76, 216. Bladderwort, 104. Blood, circulation of, 23, 171. Blood corpuscles, red, 34, 170; white, 170. Blood crystals, 173, 174. Boreel, 20.