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Achromatic acid adjustment Angle of Aperture angular aperture Animal Animalcules antheridia antherozoids appearance areola attached binary subdivision Binocular body Canada balsam cavity cells centre cilia colour Condenser consists containing convenient convex cover cuticle cyclosis diameter Diatoms disk distance distinct elongated employed endochrome envelope extremely Eye-piece filaments fluid focus Foraminifera frond frustules gelatinous genus Glycerine gonidia illumination inch Infusoria instrument interior Journ layer lens lenses light liquid magnifying power markings membrane ment Microsc Microscope Microscopist milled-head minute mode mounted movement Object-glass oblique observer obtained Opaque objects ordinary organs particles peculiar Plants plate portion present primordial cell primordial utricle prism Prof prothallium protoplasm Quart rays refraction seen separated side slide sometimes species specimens spores stage stem stomata structure substance surface thickness thin glass tion tissue transparent transverse tube usually utricle valves Vegetable Volvox whilst Zoophytes zoospores
Page 543 - Suppose a human mason to be put down by the side of a pile of stones of various shapes and sizes, and to be told to build a dome of these, smooth on both surfaces, without using more than the least possible quantity of a very tenacious, but very costly, cement, in holding the stones together. If he accomplished this 42 well, he would receive credit for great intelligence and skill. Yet this is exactly what these little 'jelly specks' do on a most minute scale; the 'tests' they construct, when highly...
Page 470 - Supposing it to rest upon its convex surface, it consists of a lower plate, shaped like a deep saucer or watch-glass; of an upper plate, which is sometimes flat, sometimes more or less watch-glass-shaped; of the oval, thick-walled, flattened corpuscle, which connects the centres of these two plates ; and of an intermediate substance, which is closely connected with the under surface of the upper plate, or more or less...
Page 324 - ... preserved by Saxo. But to the origin of the rest the genealogies give us no clue. If they were all of royal origin — and apparently they did claim divine descent — the Angli must have possessed a numerous royal class ; and we are scarcely justified in denying that this may have been the case1. On the other hand it is by no means impossible that some of them were sprung from foreign peoples, such as the Danes, Swedes or Warni. But what we may regard as practically certain is that the individual...
Page 326 - Point, the bottoms of which are literally covered in the first warm days of spring with a ferruginous-coloured mucous matter, about a quarter of an inch thick, which, on examination by the microscope, proves to be filled with millions and millions of these exquisitely beautiful siliceous bodies. Every submerged stone, twig, and spear of grass, is enveloped by them ; and the waving plume-like appearance of a filamentous body covered in this manner, is often extremely elegant.
Page 797 - The slices thus treated appear of a darkish amber colour, very transparent, and exhibit the structure, when existing, most clearly. We have obtained longitudinal and transverse sections of coniferous wood from various coals in this way. The specimens are best preserved in glycerine in cells ; we find that spirit renders them opaque, and even Canada balsam has the same defect. Schulz states that he has brought out the cellulose reaction with iodine, in coal treated with nitric acid and chlorate of...
Page 575 - ... each thread is about eighteen inches long, in the middle the thickness of a knitting needle, and gradually tapering towards either end to a fine point ; the whole bundle coiled like a strand of rope into a lengthened spiral, the threads of the middle and lower portions remaining compactly coiled by a permanent twist of the individual threads ; the upper portions of the coil frayed out, so that the glassy threads stand separate from each other. The spicules on the outside of the coil stretch its...
Page 797 - The coal is macerated for about a week in a solution of carbonate of potash ; at the end of that time it is possible to cut tolerably thin slices with a razor. These slices are then placed in a watchglass with strong nitric acid, covered and gently heated ; they soon turn brownish, then yellow, when the process must be arrested by dropping the whole into a saucer of cold water, else the coal would be dissolved.
Page 800 - ... fragments become smaller, and calcareous mud, structureless and in a fine state of division, is in greatly preponderating proportion. One can have no doubt, on examining this sediment, that it is formed in the main by the accumulation and disintegration of the shells of globigerina — the shells fresh, whole, and living in the surface-layer of the deposit, and in the lower layers dead, and gradually crumbling down by the decomposition of their organic cement, and by the pressure of the layers...