. The microscope and its revelations. scopist could now be led astrayby such obvious fallacies as those alluded to, it is necessary tonotice them as warnings to those who have still to go through education. The best method of learning to appreciate theela*s of appearances in question is the comparison of the aspect ofglobule* of oil iii water with that of globules of water in oil, or of Mirronco/iioil Journal, vol. v. 1872, p. 14. STUDIES IN INTERPRETATION 429 bubbles of air in water or Canada ver readil made b shakin up some oil This comparison maywith water to which a lit
. The microscope and its revelations. scopist could now be led astrayby such obvious fallacies as those alluded to, it is necessary tonotice them as warnings to those who have still to go through education. The best method of learning to appreciate theela*s of appearances in question is the comparison of the aspect ofglobule* of oil iii water with that of globules of water in oil, or of Mirronco/iioil Journal, vol. v. 1872, p. 14. STUDIES IN INTERPRETATION 429 bubbles of air in water or Canada ver readil made b shakin up some oil This comparison maywith water to which a little gum has been added, so as to form an emulsion, or byDimply placing a drop of oil of turpentine (coloured with magentaor carmine) and a drop of water together upon a .slide, laying a thinglass cover over them, and then moving the cover backwards andforwards several times on the slide. Equally instructive are theappearances of an air-bubble in water and Canada balsam. The figures which illustrate the appearance at various points JB. FIG. 366.—Air-bubbles in (1) water ; (2) Canada balsam; (3) fat-globules in water. of the focus of an air-bubble in water and Canada balsam, and of afat-globule in water, may be thus illustrated, vi/. a diaphragm ofabout § of a mm. being placed at a distance of 5 mm. beneath thestage, and the concave mirror exactly centred. Air-babbles in —Xo. 1 (fig. 366) represents the differentappearances of an air-bubble in water. On focussing the objectiveto the middle of the bubble (B), the centre of the image is seen to bevery bright—brighter than the rest of the^field. It is surrounded bya greyish zone, and a somewhat broad black ring interrupted by one 43O MANIPULATION AND PRESERVATION OF THE MICROSCOPE or more brighter circles. Round the black ring are again one ormore concentric circles (of diffraction), brighter than the field. ( )n focussing to the bottom of the bubble (A) the central whitecircle diminishes and becomes brighter; its marg
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Keywords: ., bookcentury1900, bookdecade1900, booksubjectmicrosc, bookyear1901
