Adrien Guébhard

“ A variety of colored liquids are at our disposal, and, with a little alcohol, or a trace of glycerine or sugar, we may modify insensibly the density of the liquids, reduce the action of gravity to a minimum, and have at will ascending or descending currents. The last are generally easiest to obtain. Fig. 3 represents a simple apparatus for the experiment, the operation of which is dependent on the familiar principle of the siphon: we have only to raise the level of the colored liquid in the glass to change the rate of flow as we may wish. ”

“ The periodical November meteors form a real ring of planetary fragments around the earth; everything seems to prove that the milky way is nothing but a gigantic ring of cosmic dust, of which our sun and its satellites are only a few grains ”

“ But, if they pass each other, only grazing their edges, they will merely change shape without breaking and without getting out of the way, and then immediately bound back to their original form like an India rubber spring. ”

“ Everybody has seen some adroit smoker throw from his mouth or his pipe pretty, white wreaths, whose whirling vapors it was a pleasure to follow in the air. [1] It is a fact of daily observation that a drop of soap and water dropping from the end of the fingers spreads out in the basin into the form of a perfect ring that gradually increases as it descends toward the bottom. ”

“ In water, effects of exquisite beauty may be produced directly without passing through the intermediate phases, by means of taps on the membrane of the apparatus. The experiment may again be simplified by forming with the membrane itself the bottom of the vessel, and using for an orifice a hole pierced in a disk which has been forced down tight into the middle of the tube. ”

“ The box is filled from the mouth at the hole in the upper side.
means of a slight blow cause wreaths several inches in diameter, exhibiting the structural details of the liquid rings, to shoot out to a considerable distance. A soap-bubble filled with smoke produces similar effects when it bursts; and a cubic box made of playing-cards (Fig. 5) will enable us to study, with the help of tobacco-smoke, how little influence the shape of the opening has upon the rings which we drive out through the hole at which we have tilled the box. We may make the hole square or rectangular ”

“ Attack it as quickly as you will, says Professor Tait, cut at it with the sharpest knife, you can never sever it or mar it; but, flying away or enveloping the material object, it remains whole, always itself; and, when we consider its wonderful properties, we need hardly be surprised that philosophers have aspired to build up upon it theories of the constitution of matter, and of the origin of all the physical forces, from gravitation to electricity. ”

“ Nature herself sometimes produces this phenomenon without any human intervention, and shows us the vortices of the ignis fatuus, to which the middle ages attached so many poetical legends, rising on summer evenings from the stagnant waters of marshes. ”

“ This power of resistance, or power of annular elasticity, is the most striking characteristic of these singular forms, real magazines of energy, in which all the living primitive force collects itself under the influence of external friction. Theoretically, the vortical movement, in a perfect fluid, can neither be created nor destroyed; eternal as matter itself, it has neither beginning nor end. ”

“ Any one who has pursued a course in chemistry may remember the beautiful experiments in which bubbles of phosphoretted hydrogen take fire spontaneously as they rise to the surface of the basin, and develop superb wreaths of white fumes. ”

“ Imperceptible grains of coloring substance, put upon the surface of the water, immediately give rise to fine descending trains, which permit us to detect in the phenomena of solution the same character of intermittence and discontinuity that marks that of osmose. ”

“ The laws of nature, however, frequently reveal themselves best in the infinitely little; and I have made my first observations toward a new study in watching the filiform currents produced during the osmotic interchange of two liquids through the pores of a membrane. ”

“ Observation shows, together with a delicacy of design in the shaft, and a transparency which nothing can excel, fine horizontal striæ passing from one volute to another, and marking with exceeding neatness the number and divergence of the rollings. ”

“ This instrument gives at each expulsion of the colored ring a corresponding return ring, a kind of negative ring, that descends clear in the interior of the colored liquid, or vice versa, if it is the liquid in the upper part that has been colored. The same phenomena appear when smoke is used, as in Fig. 4. We may dispense with all apparatus and Let fall from the height of about an inch a lightly tinted drop into a still colorless mass. ”