142 PHILOSOPHICAL PERIODICALS. the colour shifts towards red ; from 490 to 460 pp. there is no change ; beyond 460 pp the colour again shifts redwards. The degree of qualitative change is not proportional to intensity of stimulus. Theory follows in a later paper.] G. J. Schoute. ' Abnorme Augenstellungbeiexcentrischgelegener Pupille.' [Description of case ; explanation and measurement of anomaly.] M. Meyer. 'Nachtragzumeiner Abhandlung. "UeberTonverschmelzung und die Theorie der Consonanz."' C. Stumpf. ' Erwiderung.' [Continua- tion of controversy. Stumpf holds that clang analysis is rendered more or less difficult, according to conditions, by consonance ; Meyer that un- musical persons are readier to say ' one tone ' when the impression of consonance is present than when it is absent. No new facts are alleged.] Litteraturbericht. Bd. xviii., Heft 5 und 6. C. Stumpf und M. Meyer. ' Maassbestimmungen ueber die Eeinheit consonanter Intervalle.' [De- siderata : experiments with successive tones, in ascending and descending order ; with simultaneous tones ; with simple tones and clangs. Previous Literature. Chapters i., ii. (S.), Experiments with the major and minor third. Chapter iii. (M.), Experiments with major third, fifth and octave. Chapter iv. (S. and M.), Uniformities in the results of these last experi- ments. Chapter v. (S.), Comparison of the new with older results. Con- tains a severe criticism of Schischmanow. Chapter vi. (S.), Remarks of the subjects during the experiments. Chapter vii. (S.), Explanations. (1) The judgment of purity is based upon a ' feeling for purity,' or rather a ' feeling for impurity '. With augmented intervals there is a feeling of strain, of sharpness ; with diminished, a feeling of bluntness, dullness, flatness. The feeling is now primary, the judgment secondary ; phylogenetically, .a judgment of deviation from degree of fusion is primary. (2) Impurity can be cognised earlier than its direction ; evidently, since the unpleasant feeling is common to both directions. (3) The major third is augmented, the minor diminished, in judgments of subjective purity. The reason is the aesthetic need of expression, of emphasising the characteristic. (4) Fifths and, still more, octaves, are similarly augmented ; especially in .ascending succession. The reason is that the energy of progression is thereby emphasised. From successive, this augmentation has passed over to simultaneous tones. (5) Succession is better than simultaneity for judgments of purity, because these judgments depend on feeling; simultaneity reduces distinctness (fusion), and so obstructs the judgment. {6) Clangs rich in overtones give uncertain judgments of purity. This is strange only to those who hold Helmholtz's theory of consonance. (7) The fifth has the advantage over other intervals in these judgments ; the rest stand on the same level. The current belief to the contrary is rooted in speculation, not in fact.] T. Lipps. ' Baumaesthetik und geometrisch-optische Taeuschungen, i.' [Elaborate reply to Heyman's criticism.] Besprechung. [Martius on Jodl's Lehrbuch.] Litteratur- bericht. PHILOSOPHISCHE STUDIEN. Bd. xiv., Heft. 3. H. Bruns. ' Zur Collect! v-Masslehre.' [Presents and gives numerical tables for an im- proved method of investigating collective objects (Fechner).] K. Marbe.
- Die stroboskopischen Erscheinungen.' [Historical : the invention of
the stroboscope ; Fischer's investigation and its results (1886). Deriva- tion of the laws of stroboscopy from Talbot's law. Restatement of the author's theory of this law, and critique of Witasek (Weber's law may be employed as explanatory principle) and of Fick and Schenck (eye- movement theory untenable).] R. Mueller. ' Ueber Raumwahrnehmung beim monocularen indirecten Sehen.' [Historical : Descartes to Wundt ; Kirschmann's hypothesis of the function of dispersion circles (parallax of indirect vision). Experiments with falling balls (black and white, seen
