Gratings Sentence Examples

This opisthodomus was completely fenced in with bronze gratings; and the excavators believe it to have been adapted for use as an adytum (shrine).

This method is frequently adopted in combined schemes of heating and ventilating; the fresh air is warmed by being passed over their surfaces previously to being admitted through the gratings into the room.

The houses, built of stone and whitewashed, are square, substantial, flat-topped buildings, presenting to the street bare walls, with a few slits protected by iron gratings in place of windows.

It is true that in 1823 Fraunhofer, inspired by his observations upon gratings, had very nearly hit the mark.'

Abbe published a somewhat more complete investigation, also founded upon the phenomena presented by gratings.

But although the argument from gratings is instructive and convenient in some respects, its use has tended to obscure the essential unity of the principle of the limit of resolution whether applied to telescopes or microscopes.

He constructed gratings up to 340 periods to the inch by straining fine wire over screws.

Subsequently he ruled gratings on a layer of gold-leaf attached to glass, or on a layer of grease similarly supported, and again by attacking the glass itself with a diamond point.

The best gratings were obtained by the last method, but a suitable diamond point was hard to find, and to preserve.

In different gratings the lengths of the spectra and their distances from the axis were inversely proportional to the grating interval, while with a given grating the distances of the various spectra from the axis were as i, 2, 3, &c. To Fraunhofer we owe the first accurate measurements of wave-lengths, and the method of separating the overlapping spectra by a prism dispersing in the perpendicular direction.

He described also the complicated patterns seen when a point of light is viewed through two superposed gratings, whose lines cross one another perpendicularly or obliquely.

So far as the application to gratings is concerned, the same conclusion may be derived from (2).

It is possible to prepare gratings which give a lateral spectrum brighter than the central image, and the explanation is easy.

We will now consider the important subject of the resolving power of gratings, as dependent upon the number of lines (n) and the order of the spectrum observed (m).

There is clearly no theoretical limit to the resolving power of gratings, even in spectra of given order.

Suppose two similar and accurately ruled transparent gratings to be superposed in such a manner that the lines are parallel.

The latter found that certain gratings exercised a converging power upon the spectra formed upon one side, and a corresponding diverging power upon the spectra on the other side.

The explanation of the difference of focus upon the two sides as due to unequal spacing was verified by Cornu upon gratings purposely constructed with an increasing interval.

Rowland to his brilliant invention of concave gratings, by which spectra can be photographed without any further optical appliance.

Curvature of the primary focal line having a very injurious effect upon definition, it may be inferred from the excellent performance of these gratings that y is in fact small.

For absolute determinations of wave-lengths plane gratings are used.

Since the time of Fraunhofer many skilled mechanicians have given their attention to the ruling of gratings.

In Rowland's dividing engine the screws were prepared by a special process devised by him, and the resulting gratings, plane and concave, have supplied the means for much of the best modern optical work.

At the present time excellent reproductions of Rowland's speculum gratings are on the market (Thorp, Ives, Wallace), prepared, after a suggestion of Sir David Brewster, by coating the original with a varnish, e.g.

It is to be desired that transparent gratings should be obtained from first-class ruling machines.

In this way the principal features of the phenomenon are accounted for, and Schuster has shown further how to extend the results to spectra having their origin in prisms instead of gratings.

When the cage arrives at the surface, or rather the platform forming the working top above the mouth of the pit, it is received upon the keeps, a pair of hinged gratings which are kept in an inclined position over the pit-top by counterbalance weights, so that they are pushed aside to allow the cage to pass upwards, but fall back and receive it when the engine is reversed.

Henry Draper's most important contributions to science were made in spectroscopy; he ruled metal gratings in 1869-1870, made valuable spectrum photographs after 1871, and proved the presence of oxygen in the sun in a monograph of 1877.

Rowland's efforts the construction of gratings has been improved to such an extent that their use is becoming universal whenever great power or accuracy is required.

At present we have still to content ourselves with a much diminished intensity of light when working with gratings, but there is some hope that the efforts to concentrate the light into one spectrum will soon be successful.

The resolving power in the case of gratings is simply mn, where m is the order of spectrum used, and n the total number of lines ruled on the grating.

Especially when large gratings are employed do we find that the electric arc alone seems sufficient to give vibrations of the requisite power.

In grating spectroscopes both plane and concave gratings are employed in connexion with a collimator and observing telescope.

Mine waters generally contain the copper in this form, and it is extracted by conducting the waters along troughs fitted with iron gratings.

In 1882, before the Physical Society of London, he gave a description of the diffraction gratings with which his name is specially associated, and which have been of enormous advantage to astronomical spectroscopy.

These gratings consist of pieces of metal or glass ruled by means of a diamond point with a very large number of parallel lines, on the extreme accuracy of which their efficiency depends.

These outlets should be faced with mason work, and guarded with iron gratings.

This is a so-called cross grating formed by two perpendicular gratings.

We design distorted diffraction gratings that simulate the effects of long propagation distances in a short instrument.

Our preliminary results indicate that cortical cells may be responding to temporal cues in flickering or moving gratings.

Leaves and flower heads could easily block your drains if you have any gratings in the area.

The most recent results are shown below as graphs 14 and 15 for the low and high energy gratings respectively.

But, except perhaps in the case of very fine gratings, it is probable that the error thus caused is insignificant; for the incorrect estimation of the secondary waves will be limited to distances of a few wave-lengths only from the boundary of opaque and transparent parts.