The illumination of the field is given by a lamp near the object glass, controlled by a switch near the micrometer.
Owing to the variable illumination of the selenium thus produced, the resistance of the latter, and therefore the intensity of the current sent through the line to the receiving station by the battery, will be altered accordingly.
This is the main transpiring tissue, and is protected from direct illumination and consequent too great evaporation.
2, B), since there is no difference in the illumination and other external conditions, --------
The most constantly occurring changes that beset a plant are connected with illumination, temperature, moisture, and contact with foreign bodies.
Cases of pallor due to too intense illumination and destruction of chlorophyll must also be distinguished.
If on the other hand the number of zones be odd, the effects conspire; and the illumination (proportional to the square of the amplitude) is four times as great as if there were no obstruction at all.
The process of augmenting the resultant illumination at a particular point by stopping some of the secondary rays may be carried much further (Soret, Pogg.
Such a plate has the power of a condensing lens, and gives an illumination out of all proportion to what could be obtained without it.
In like manner we may find the illumination in any other direction, and it is obvious that it vanishes when sin 0 is any multiple of A/a.
Thus, if x = R cos 4), C =,r2R2J1(pR) pR and the illumination at distance r from the focal point is 4T2 r 21rRr1 fX (2 fKr) a J The ascending series for J 1 (z), used by Sir G.
The illumination at B due to P then becomes comparatively small, indeed for some forms of aperture evanescent.
On either side of any one of them the illumination is distributed according to the same law as for the central image (m = o), vanishing, for example, when the retardation amounts to (mn t 1)X.
The expression (5) gives the illumination at due to that part of the complete image whose geometrical focus is at =o, the retardation for this component being R.
If the slit is of 'constant width and we require the illumination at various points on the screen behind it, we must regard the arc of the curve as of constant length.
Outside the cone of 54° there will be faint illumination; within it, no secondary rays will be transmitted to the eye.
Teacher had been with me nearly two weeks, and I had learned eighteen or twenty words, before that thought flashed into my mind, as the sun breaks upon the sleeping world; and in that moment of illumination the secret of language was revealed to me, and I caught a glimpse of the beautiful country I was about to explore.
They do not see that the role of the natural sciences in this matter is merely to serve as an instrument for the illumination of one side of it.