The mistake, shown in all the old maps of Australia, had originated in a curious optical illusion.
In length by any mirrors which can be practically constructed would be like attempting optical experiments with mirrors one-hundred-thousandth of an inch in diameter.
Malt, tinware, flour and grist-mill products, boilers, stoves and ranges, optical supplies, wall-paper, cereals, canned goods, cutlery, tin cans and wagons are manufactured, and there are also extensive nurseries.
His optical investigations are perhaps the subject in which he most contributed to the progress of science; and the lucidity of exposition which marks his Dioptrics stands conspicuous even amid the generally luminous style of his works.
Dark coloured micas are strongly pleochroic. Accurate determinations of the optical orientation, as well as the symmetry of the etching figures on the cleavage planes, seem to suggest that the micas, except muscovite, may be anorthic rather than monoclinic in crystallization.
His researches extended to almost every branch of physical science, but his most important work was of an optical character.
In their optical characters the micas exhibit considerable variations.
By this time he had ceased to devote himself to pure mathematics, and in company with his friends Mersenne and Mydorge was deeply interested in the theory of the refraction of light, and in the practical work of grinding glasses of the best shape suitable for optical instruments.
R, Optical section of leptoid (sieve-tube segment) of Phanerogam, with two proteid (companion) cells.
Etymologically the word implies that the messages are written, but its earliest use was of appliances that depended on visual signals, such as the semaphore or optical telegraph of Claude Chappe.
The radiations interfere in an optical sense of the word, and in some directions reinforce each other and in other directions neutralize each other, so making the resultant radiation greater in some directions than others.
D, Further advanced trochosphere (optical section).
The larger ones polarize light, have angular outlines like those of crystals, and may even show twinning and definite optical properties by which they can be identified as belonging to felspar, augite or some other rock-forming mineral.
61, p. 444), and the instrument contains many elegant mechanical and optical details due to Horace Darwin and Messrs Zeiss respectively.
The distance between the centres of the two spectrographs shall be equal to the distance between the optical axes of the two viewing microscopes.
To optical ones can be performed with somewhat shorter waves.
- Optical Section of a Statocyst of Octorchis.
L, Optical section of cell of parenchyma in the same moss.
He now employed himself in making optical glasses, and in engraving on metal, devoting his spare time to the perusal of works on mathematics and optics.
D, Optical section of a branch of organs are present to the number of a single pair per somite, and are commonly present in the majority of the segments of the body, failing often among the Oligochaeta in a varying number of the anterior segments.
The most important subjects of his inquiries are enumerated by Forbes under the following five heads: - (1) The laws of polarization by reflection and refraction, and other quantitative laws of phenomena; (2) The discovery of the polarizing structure induced by heat and pressure; (3) The discovery of crystals with two axes of double refraction, and many of the laws of their phenomena, including the connexion of optical structure and crystalline forms; (4) The laws of metallic reflection; (5) Experiments on the absorption of light.
He invented the wheel barometer, discussed the application of barometrical indications to meteorological forecasting, suggested a system of optical telegraphy, anticipated E.F.F.
His studies of the eruptive rocks of Corsica, Santorin and elsewhere; his researches on the artificial reproduction of eruptive rocks, and his treatise on the optical characters of felspars deserve special mention; but he was perhaps best known for the joint work which he carried on with his friend Michel Levy.
This tetrahedral configuration is based on the existence of only one methylene dichloride, two being necessary if the carbon valencies were directed from the centre of a plane square to its corners, and on the existence of two optical isomers of the formula C. A.
The actual finiteness of A imposes a limit upon the separating or resolving power of an optical instrument.
In the optical examination we may, if we prefer it, polarize the primary light; but it is usually more convenient to analyse the scattered light.
S, Optical section of part of thick-walled stereid of Phanerogam, with almost obliterated cavity and narrow slit-like oblique pits.
B, The diblastula has become a trochosphere by the development of the ciliated ring y r (optical section).
The proof of this statement rests on the fact that if the hydrogen atoms were not co-planar, then substitution derivatives (the substituting groups not containing asymmetric carbon atoms) should exist in enantiomorphic forms, differing in crystal form and in their action on polarized light; such optical antipodes have, however, not yet been separated.
Other physical properties of these solutions, such as density, colour, optical rotatory power, &c., like the conductivities, are additive, i.e.
Thus in 1857 he went to Peru in order to determine the magnetic equator; in1861-1862and 1864, he studied telluric absorption in the solar spectrum in Italy and Switzerland; in 1867 he carried out optical and magnetic experiments at the Azores; he successfully observed both transits of Venus, that of 1874 in Japan, that of 1882 at Oran in Algeria; and he took part in a long series of solar eclipse-expeditions, e.g.
We may conveniently commence with them on account of their simplicity and great importance in respect to the theory of optical instruments.
The contraction of the diffraction pattern with increase of aperture is of fundamental importance in connexion with the resolving power of optical instruments.
4, AB represents the axis of an optical instrument (telescope or microscope), A being a point of the object and B a point of the image.
A much more valuable practical result of Brewster's optical researches was the improvement of the British lighthouse system.
A, Diblastula phase (optical section).
There is a considerable export of quartz crystal, commercially known as "Brazilian pebbles," used in optical work.
The plane surfaces and XX are composed of a bronze of very close texture, which appears capable of receiving a finish having almost the truth and polish of an optical surface.