Bauhaus-Universität Weimar

Experimental Psychology: A Manual of Laboratory Practice, Vol. II: Quantitative Experiments, part 2: Instructor's Manual
Titchener, Edward B.
§ 18. Demonstrations of Weber s Latv 
8 7 
Photometrical Measurements, 1900; cf. refs, in Baldwin’s Diet., 
ii., 298. If the students in the Course are taking a concomitant 
course in experimental physics (vol. i., I. M., xxv.), special ar¬ 
rangements may be made with the Instructor in Physics to intro¬ 
duce the typical photometric exercises. 
Some Experiments on Colour Photometry.—The following experi¬ 
ments may be assigned to interested students. 
(1) Martius' Method. Two similar rings are cut from the coloured 
paper to be investigated, and are pasted with great care upon black and 
white discs of the same size. The two ri iged discs 
are then mounted upon a colour mixer. If, now, 
the coloured paper is brighter than the surround¬ 
ing grey, the grey of the inner disc will, under 
steady fixation, darken ; if it is darker, the inner 
grey will lighten. If the brightnesses of grey and 
colour are equal, the O will say * equal ’ or ‘ doubt¬ 
ful.’—For full account of method 1 and apparatus, ^ Martius’disc 
see G. Martius, Beitr. z. Psych, u. Phil., i., 1896, 
104 ff. ; cf. ibid., 1897, 161 ff. ; iii. Internat. Congress, 1897, 183 ff. 
(2) Rivers' Method. If a compound disc of two colours or of a colour 
and a grey be set into such rapid rotation that mixture is complete, and 
a light w'ooden rod be passed across the surface of the disc, the rod will 
ordinarily leave behind it on the disc a number of parallel bands in the 
colours of the original components (or of the one colour component and 
of the complementarily tinged grey) alternately arranged. This phe¬ 
nomenon is called the Münsterberg-Jastrow effect (Jastrow, A. J., iv., 
1891, 201 ; Sanford, Course, 167 ; E. B. Holt, Harvard Stud., L, 1903, 
167). When, however, the grey and the colour of such a compound 
disc are of equal brightness, the bands do not appear.—For method and 
materials, see W. H. R. Rivers, Journ. Physiol., xxii., 1897, 137 ff. 
(3) Flicker Photometry. The general principle or postulate which 
underlies flicker photometry is that the point at which intermittent R 
give rise to a continuous S depends on brightness and not on colour 
tone. A good deal of work has been done in recent years, and the 
method bids fair to supplant the other methods proposed for colour pho¬ 
tometry. So far, however, the results have not been properly co-ordinated, 
and theory has not settled down to anything like universal acceptance. 
The literature is easily accessible ; and the author therefore lists the 
1 Note the remark, 109 f., that the pairing of the series is not necessary.


Sehr geehrte Benutzer,

aufgrund der aktuellen Entwicklungen in der Webtechnologie, die im Goobi viewer verwendet wird, unterstützt die Software den von Ihnen verwendeten Browser nicht mehr.

Bitte benutzen Sie einen der folgenden Browser, um diese Seite korrekt darstellen zu können.

Vielen Dank für Ihr Verständnis.