Soc., 1890, 47, p. 364), who found that a film of olive oil spread over the surface of water produced a perceptible effect on small floating pieces of camphor, at places at which the thickness of the film was io 6 X10 -8 cms., but produced no perceptible effect at all at places where the thickness of the film was 8.1 X10 -8 cms. Thus a certain phenomenon, of the nature of capillary action, is seen to depend for its existence on the linear dimensions of the film of oil; the physical properties of a film of thickness Io 6Xio 8 cms. are found to be in some way qualitatively different from those of a film of thickness 8.1 X io 8 cms. Here is proof that the film of oil is not a continuous homogeneous structure, and we are led to suspect that the scale on which the structure is formed has a unit of length comparable with 8 X10 -8 cms. The probability of this conjecture is strengthened when it is discovered that in all phenomena of this type the critical length connected with the stage at which the phenomenon changes its nature is of the order of magnitude of 10 -8 cms.
In dry weather, since it promotes capillary action by reducing the soil spaces.
The vessel is completely filled with mercury, the capillary sealed, and the vessel weighed.
Wide, the water from the pathways is soaked up on each side by capillary attraction, and in this way the roots secure a sufficient supply.
From the bottom there leads P another fine tube, bent upwards, and then at right angles so as to be at the same level as the capillary branch.
He published many physical memoirs on electricity, the dilatation of liquids by heat, specific heats, capillary attraction, atomic volumes &c. as well as a treatise in 4 volumes on Fisica di corpi ponderabili (1837-1841).
In the breeding season the male deposits drops of sperm on a sheet of webbing, picks it up in these flasks by means of capillary attraction and carries it about until he falls in with a female.
Capillarity and Surface Tension.-Reference should be made to the article Capillary Action for the general discussion of this phenomenon of liquids.
The apparatus devised by Ramsay and Shields consisted of a capillary tube, on one end of which was blown a bulb provided with a minute hole.
This reflection is suggested by the following articles: Aether; Molecule; Capillary Action; Diffusion; Radiation, Theory Of; and others.
In some species (Spengelidae) there is a long capillary vermiform extension of the stomochord in front.
De Phys., Paris, 1900, p. 561) that the true effect of magnetization is liable to be disguised by secondary or parasitic phenomena, arising chiefly from polarization of the electrodes and from local variations in the concentration and magnetic condition of the electrolyte; these may be avoided by working with weak solutions, exposing only a small surface in a non-polar region of the metal, and substituting a capillary electrometer for the galvanometer generally used.
According to Rogowicz and Heidenhain, certain substances increase the quantity of lymph given off from a part by acting upon the cells of the capillary wall; they hold, in fact, that these substances are true lymphagogues.
Mile of Warsaw in 1828, who termed it a "hydrostatic air-pump without cylinders, taps, lids or stoppers," this is attained by using, both for the inlet and the outlet, vertical capillary glass tubes, soldered, the former to somewhere near the bottom, the latter to the top of the vessel.
P. 211, Paris, 1869) proposed an equation of the form (p+po)(v - b) =RO, in which the effect of the size of the molecules is represented by subtracting a quantity b, the " covolume," from the volume occupied by the gas, and the effect of the mutual attractions of the molecules is represented by adding a quantity po, the internal pressure, to the external pressure, p. This type of equation, was more fully worked out by van der Waals, who identified the internal pressure, po, with the capillary pressure of Laplace, and assumed that it varied directly as the square of the density, and could be written a/v 2 .
The vessel is filled by placing the capillary in a vessel containing the liquid and 6 gently aspirating.
Experiments by the capillary tube method have shown that the viscosity varies more nearly as 0 1, but indicate that the rate of increase diminishes at high temperatures.
P, Osmotic or capillary pressure.
The setae are either entirely capillary or there are in addition some sigmoid setae even with bifid free extremities.
The products obtained by the distillation of petroleum are not in a marketable condition, but require chemical treatment to remove acid and other bodies which impart a dark colour as well as an unpleasant odour to the liquid, and in the case of lamp-oils, reduce the power of rising in the wick by capillary attraction.
Ulrich Kreusler generates the carbon dioxide in a separate apparatus, and in this case the tube is drawn out to a capillary at the end (a).
The capillary tube can be raised or lowered at will by running a magnet outside the tube, and the heights of the columns are measured by a cathetometer or micrometer microscope.
Heidenhain, on the other hand, rejected entirely the filtration view of lymph-formation, believing that the passage of lymph across the capillary wall is a true secretion brought about by the secretory function of the endothelial plates.
Thus, while increased pressure in the blood or lymph vessels may be one factor, and increased permeability of the capillary endothelium another, increased osmotic pressure in the tissues and lymph is probably the most important in the production of dropsy.
4), consists of a vertical capillary Pump. glass tube a of about 1 mm.
The simplest assumption which suffices to express the small deviations of gases and vapours from the ideal state at moderate pressures is that the coefficient a in the expression for the capillary pressure varies inversely as some power of the absolute temperature.
4, which has a capacity of about 35 cc., provided with a capillary tube at the top, and a bent tube about 6 mm.
Solids may be directly admitted to the tube from a weighing bottle, while liquids are conveniently introduced by means of small stoppered bottles, or, in the case of exceptionally volatile liquids, by means of a bulb blown on a piece of thin capillary tube, the tube being sealed during the weighing operation, and the capillary broken just before transference to the apparatus.
Acting on a principle quite different from any previously discussed is the capillary hydrometer or staktometer of Brewster, which is based upon the difference in the surface tension and density of pure water, and of mixtures of alcohol and water in varying proportions.
The capillary hydrometer consists simply of a small pipette with a bulb in the middle of the stem, the pipette terminating in a very fine capillary point.
The point of the rostrum is pressed against the surface to be pierced; then the stylets come into play and the fluid food is believed to pass into the mouth by capillary attraction.