What people are saying - Write a review
We haven't found any reviews in the usual places.
Other editions - View all
Achromatic acid angle angular aperture animal Animalcules antheridia appearance areolae arrangement attached Binocular body calcareous Canada balsam canals cavity cells centre chambers cilia colour consists convex cover curious diameter Diatomaceae Diatoms disk distance distinct employed endochrome examination extremely Eye-piece fibres filaments fluid focus Foraminifera frustules furnished genus glass Glycerine gonidia illumination inch Infusoria Insects instrument Journ larva layer lens lenses light liquid magnifying power membrane ment Microsc Microscope Microscopist minute mode mounted º º object Object-glass oblique observed obtained ordinary organs pair particles pass peculiar Plants plate portion present prism Prof protoplasm rays refraction resembling Rotifera scale seen segments separated shell shown side slide sometimes species specimens Spherical Aberration spicules stage stem Stereoscopic stomata structure substance surface thickness thin tion tissue transparent transverse tube usually utricle valves Vegetable whilst Zoophytes zoospores
Page 541 - 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 795 - 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 573 - ... 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 795 - 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 798 - ... 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...