_ And, that _Red is an impression on
the Retina of an oblique and confus'd pulse of light, whose strongest part
precedes, and whose weakest follows._
Which proprieties, as they have been already manifested, in the Prisme and
falling drops of Rain, to be the causes of the colours there generated, may
be easily found to be the efficients also of the colours appearing in thin
_laminated_ transparent bodies; for the explication of which, all this has
been premised.
And that this is so, a little closer examination of the _Phaenomena_ and
the _Figure_ of the body, by this _Hypothesis_ will make evident.
For first (as we have already observed) the _laminated_ body must be of a
determinate thickness, that is, it must not be thinner then such a
determinate quantity; for I have always observ'd, that neer the edges of
those which are exceeding thin, the colours disappear, and the part grows
white; nor must it be thicker then another determinate quantity; for I have
likewise observ'd, that beyond such a thickness, no colours appear'd, but
the Plate looked white, between which two determinate thicknesses were all
the colour'd Rings; of which in some substances I have found ten or twelve,
in others not half so many, which I suppose depends much upon the
transparency of the _laminated_ body. Thus though the consecutions are the
same in the scumm or the skin on the top of metals; yet in those
consecutions in the same colour is not so often repeated as in the
consecutions in thin Glass, or in Sope-water, or any other more transparent
and glutinous liquor; for in these I have observ'd, _Red, Yellow, Green,
Blue, Purple; Red, Yellow, Green, Blue, Purple; Red, Yellow, Green, Blue,
Purple; Red, Yellow, &c.
Pages:
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191