Here I present some optical instruments manufactured in present-day France, i.e. various types of microscope, monocrometer, projector, microcontroller, refraetometer, spectrophotometer, gastroflex, clinometer, etc.
The current distribution of the Krebs amalgam type chlorine cell, which is one of the most important types in the electrolysis of the sodium chloride solution by the amalgam process, was, analyzed and calculated by the elliptic integral of the third kind. For convenience' sake, the resistance of the graphite anode was neglected, and the chemical polarization was considered to take a constant value at each point on the electrode surface. The potential is represented as follows. _??_ and _??_ where α, β, γ, _??_, a and b are the constants, and V0* is the ohmic voltage drop in the solution.
A dynamic condenser electrometer of probe type was constructed and its operating characteristics were investigated. Such an electrometer may be veryuseful in a measurement of the surface potential distributions over an area, or, in some cases, in a work on a specimen which is too small to be measured with the condenser electrometer of ordinary type. The operating sensitivity of ca. ± 10m V was attained with a vibrating probe of about 1mm diameter. Measuring the capacity charge by Inoue circuit, the upper limit of sensitivity was estimated to be a few millivolts. The resolving power was then examined by probing a goldplated surface partly covered with a thin foil of tin. It was found that the probe could fairly distinguish the inhomogeneity in surface potential so far as its extension is larger than or comparable with the cross-sectional area of the vibrating probe. As an example of a practical application, an obliquely cut surface of a selenium rectifier wasi examined. The tripple, layers of surface metal, selenium and base metal were clearly recognized.
Critical pressures for cavitation due to dynamic action on one hand and for the fracture, under quasistatically diminishing pressure on the other, in distilled water containing dissolved air, were compared. Also critical conditions for cavitation in distilled water under various total pressures were examined. Critical pressures for the rupture in water of equal temperature and air content were not the same where the method of pressure reduction was different. It was concluded from this fact that formation of vapour pockets in cavitation is not to be attributed to local pressure reduction alone due to dynamic action of the liquid.
Various orientations of photolytic silver were examined by the electron diffraction method and discussed of their origins. Some orientations were attributed to the aggregation of interstitial silver ions. The other orientation, Which was found just beneath the surface was due to Fcenters. The former contains parallel orientation and Berry's orientation, and the latter was (100) orientation of silver on (111) innerface of silver bromide. In the course of photolysis, intermidiate crystal was also found, which showed cubic system having the lattice constant of 6.55 A. The activation energy of interstitial silver ion alone was calculated as about 0.5 eV from the time rate of photolysis of excess silver ion with temperature.
The following elements in metal samples were analysed by the direct reading spectrometer constructed by, authors: Fe, Si and Ti in aluminium samples; Si, Mn, Cu, Ni, Cr, Ti, Al, Mo, Sn, C, Mg and P in steel, samples; Cu, Fe, Ag, Sn and Bi in lead samples; Cu and Sn in zinc samples; Fe, Al, Mn in Ferro-silicon samples. The results obtained shows that the analysis by this method is very speedy and accurate compared with that by the photographic method.