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A spectrophotometric and a photometric titration method in a two-phase system for the determination of gold with ferroin is reported. Both methods are rapid and reproducible with an accuracy of ±1%. In the spectrophotometric determination Co2+, Cu2+, Ni2+, Fe3+, Zn2+, Mn2+and Cr3+do not interfere with the determination of gold and Pt4+, Pd2+, Hg2+, Ir4+and Os4+can be tolerated up to a ratio of 1:1. The titrations can also be carried out in the presence of a number of diverse ions, e.g. Ni2+, Cu2+, Co2+, Fe3+, Zn2+, Cr3+, Mn2+, without interference; the platinum metals and Hg2+cause interference but, by the use of the spectrophotometric procedure, this can be reduced.

IN THE course of efforts to obtain a recording method for measuring objecttive thresholds of vestibular stimulation, the possibility of using muscle action potentials directly from the extraocular muscles was explored. HISTORICAL REVIEW Bartels1 in 1911 published work on a method of recording the mechanical action of the extraocular muscles. The animal was placed on a rotary platform with the recording apparatus, and, with use of levers, movements of the extraocular muscles were recorded directly.Hoffmann in 19132 modified the apparatus of Bartels and recorded action potentials from the extraocular muscles, likewise directly.Köllner and Hoffmann in 19213 recorded action potentials from the extraocular muscles of the rabbit and studied the relationship of the nystagmus to ear functions.Perez-Cirera in 1932,* using a more refined apparatus than Köllner and Hoffmann, made more accurate records of the action potentials of the extraocular muscles than had previously been reported.

Yield measurements and infestation estimates of the boll weevil, Anthonomus grandis Boh., the boll worm, Heliothis zea (Boddie), and the pink boll worm, Pectinophora gossypiella (Saunders) were used to evaluate the performance of different spray-nozzle arrangements and gallonages. Results of this study indicate that one number 2 nozzle on 40-inch row centers, delivering 2 gallons of insecticide spray per acre, was as effective as any other nozzle arrangement and gallonage tested. Broad-jet nozzle types appear promising and need additional testing.