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according acid appear atmosphere average blue cause circle colour complete considered constructed containing curve density derangements derived determine direction disc disease district Donor effect elements ending equivalent examination experiment explained exponents fact factors fall feet figure function give given gold green grouped group half heat Inches increase known laws less light London Manchester mean method month motion nature object observations obtained October operation phenomena plate portion powers preceding present principal produced proved quantity rain rays reflected refraction remains remarkable rise rock roots seen shadow side Society substitutions summits suppose surface taken temperature theorem theory tion vertical waves week whole
Page 42 - tis a Sense of that Motion under the Form of Sound ; so Colours in the Object are nothing but a Disposition to reflect this or that sort of Rays more copiously than the Rest; in the Rays they are nothing but their Dispositions to propagate this or that Motion into the Sensorium, and in the Sensorium they are Sensations of those Motions under the Forms of Colours.
Page 42 - And if at any time I speak of Light and Rays as coloured or endued with Colours, I would be understood to speak not philosophically and properly, but grossly, and accordingly to such Conceptions as vulgar People in seeing all these experiments would be apt to frame. For the Rays to speak properly are not coloured. In them there is nothing else than a certain Power and Disposition to stir up a Sensation of this or that Colour.
Page 399 - The filaments in question are seen, and appear well defined, at the edges of the luminous surface where it overhangs ' the penumbra,' as also in the details of the penumbra itself, and most especially are they seen clearly defined in the details of ' the bridges,' as I term those bright streaks which are so frequently seen stretching across from side to side over the dark part of the spot. So far as I have as yet had an opportunity of estimating their actual magnitude, their average length appears...
Page 207 - ... the higher parts. There is hardly a district in Upper Styria where you will not find arsenic in at least one house, under the name of hydrach. They use it for the complaints of domestic animals, to kill vermin, and as a stomachic to excite an appetite. I saw one peasant show another on the point of a knife how much arsenic he took daily, without which, he said, he could not live ; the quantity I should estimate at two grains.
Page 46 - And are not these vibrations propagated from the point of incidence to great distances? And do they not overtake the rays of light, and by overtaking them successively do they not put them into the fits of easy reflection and easy transmission described above?
Page 203 - Eoscoe stated that all the letters received from the medical men in Styria agree in acknowledging the general prevalence of a belief that certain persons are in the habit of continually taking arsenic in quantities usually supposed sufficient to produce death. Many of the reporting medical men had no experience of the practice ; others describe certain cases of arsenic...
Page 226 - Next, to show that decomposition may be arrested artificially to the preservation of health without the destruction of vegetation; and that in these facts we have not only a surer basis in our reasonings on the origin of malaria, but an almost certain process for its ultimate and total...
Page 43 - For since colours are the qualities of light, having its rays for their entire and immediate subject, how can we think those rays qualities also, unless one quality may be the subject of and sustain another; which in effect is to call it substance. We should not know bodies for substances, were it not for their sensible qualities, and the principal of those being now found due to something else, we have as good reason to believe that to be a substance also.
Page 42 - From all which it is manifest, that if the sun's light consisted of but one sort of rays, there would be but one colour in the whole world, nor would it be possible to produce any new colour by reflections and refractions, and by consequence that the variety of colours depends upon the composition of light.