Darstellung doppelbrechender Lipoidtropfen aus dem Serum

Summary (1) Doubly refracting lipoid droplets can be demonstrated in normal and pathological sera by means of alcohol ether extraction. This is not possible with ether extraction alone.(2) These lipoid droplets can be demonstrated only, or almost only, when they are precipitated out of alcohol or ether alcohol     

Oberflächenspannung und Schallgeschwindigkeit

Summary The preceding empirical relation was found between the surface tension of liquids, the specific weight of liquids, and the velocity of sound:=6.3 · 10^{–4 3/2}. In place of the vèocity of sound can be used, with suitable changes in the equation, the compressibility or, in the case of solid substances, the elasticity of the material in question. The range of validity of this relation is so large that it is possible by means of it to calculate the surface tension of solid substances and of gases.     

Der Einfluß der Temperatur auf die Giftwirkung des DDT bei Honigbienen (Apis mellifica L.)

Summary The action of DDT on honey-bees depends to a high extent on the temperature (see graph). At 36°C (breeding temperature) DDT has a far weaker insecticidal action than at 20°C (laboratory temperature). This shows that the insecticidal properties of DDT diminish with the raise of temperature.This resistance to DDT at higher temperature is most propitious for bee-keeping and also explains the fact why in agricultural practice there has been no corroborated case of poisoning of bees, though in laboratory tests DDT avered itself to be toxic to bees.     

Darstellbarkeit doppelbrechender Lipoidtropfen aus dem Urin und pathogenetische Auffassungen der Lipoidurie

Summary (1) No double refractile Iipoid droplets can be obtained by alcohol ether extraction from urine or from urinary protein as it is possible from blood serum.(2) The conclusion is drawn that the double refractile lipoids droplets in urinary sediment do not pass through the glomeruli and therefore are not reabsorbed by the tubuli, but that they come from the own lipoproteins of the epithelial cells of renal tubuli and pass into urine by dissolution and desquamation of these cells.