ADDRESSES 59 
time should therefore have been exceptionally effective. This 
concurrence probably also fell in with a more or less perihelion 
position of the star at which time its differential effect was 
greatest. These concurrences may be the special reason for 
the greater size and distance of the major planets. 
Unbalanced elements in the ejective impulses naturally gave 
rotation to the knots, and this united with whatever rotatory 
property they already had as parts of the sun, so that there was 
a beginning of rotation at the very start. The large knots 
necessarily influenced the movements of the smaller knots that 
were shot out with them and kept near them, indeed they fully 
controlied any that remained within their “spheres of influ- 
ence”’ in the technical sense. The whirl of each bunch of knots 
sent forth by a given explosion would naturally tend to relate 
itself to a common plane and the knots would generally have a 
common direction of revolution, but reversals in some cases 
might obviously arise. Herein lies the basis of origin of the 
satellites. 
On emerging from the sun, the ejected matter suffered 
great expansion and consequent cooling, and this was followed 
by further cooling as it traversed interstellar space. Much of 
the material should therefore soon have been reduced from 
its original gaseous state to the liquid and solid states; particu- 
larly must this have been true of the more refractory material 
which makes up the greater part of the earth and probably of 
the other planets. The highly scattered matter of nebular haze 
could hardly have remained long in any other state than solid 
or liquid, but it was of course at first in minute division. As 
the temperature range of the liquid state is stnall, we may call 
the cooled matter solid, for convenience. The knots may have 
retained the gaseous state in larger degree, but the irregular 
forms they present in so many cases seem better to tally with 
the view that they too were made up largely of minutely 
divided solid matter in orbital motion. Doubtless gaseous 
matter formed some appreciable part of the knots, while a mul- 
titude of isolated molecules outside the knots doubtless pursued 
independent orbital courses about them. 
The nebula is thus conceived to have been formed in the 
main of molecules and minute bodies pursuing orbital courses 
about the solar center, and subordinately about the gravity- 
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