5 
even in the objects of different senses; as between 
the proportions of the diatonic scale and the colours 
of refracted light. They may therefore be conceived 
to have a probable existence even in objects wherein 
they have been hitherto untraced by minute inves- 
tigation*. The absence of a cranium and of ver- 
tebrz is not found to be incompatible with the ex- 
istence of a nervous system, nor the absence of a 
heart with that of a circulatory system, of a cir- 
culating fluid essential to the purposes of life and 
growth. This has been very lately traced, by the 
microscopic research of Carus, in the bodies of in- 
sects. In similar forms we constantly expect similar 
relations. But analogies excite our attention and 
admiration in direct proportion to the general dis- 
similitude of the objects in which they are traced. 
They thus burst upon our apprehension with a sud- 
den excitement of surprise, and stimulate one of the 
4 A scale of proportions in which the minutest particles of dif- 
ferent bodies unite chemically or intimately to produce com- 
pounds possessing very different and almost opposite properties, 
may be found in Dr. Thompson’s Chemistry, enlarging on the 
suggestions of Mr. Dalton. ‘‘ A remarkable instance of such a 
relation is the curious law which Bode (professor of Berlin) ob- 
served to obtain in the progression of the magnitudes of the se- 
veral planetary orbits. This law (or order of relations) was in- 
terrupted between Mars and J upiter, so as to induce him to con- 
sider a planet as wanting in that interval ; a deficiency long after- 
wards strangely supplied by the discovery of four new planets in 
that very interval, all of whose orbits conform in dimension to 
the law in question, within such moderate limits of error as may 
be due to causes independent of those on which the law itself 
ultimately rests.” Herschel’s Discourse on the Study of Natural 
Philosophy. j 
BS 
