42 THE HAMILTON ASSOCIATION. 
have each a retinue of satellites. In the Earth system the genesis 
of the moon was retarded by the solar tidal friction but not actually 
prevented. 
The phenomenon of double stars presents a special study in the 
investigation of tidal phenomena. _It is impossible that so many 
systems of double stars should have attained their relative positions 
by an accidental approach from the infinite depths of space. Tidal 
action tends to increase the eccentricity of the orbit in which the 
bodies revolve about one another and the results are much increased 
when the two bodies are not very unequal in mass. It is remarkable 
that spectroscopic observations show that the orbits of the majority 
of the known “doubles” are very eccentric. Tidal friction causes, 
too, a repulsion between the bodies and so as in the Earth-Moon 
system, the two members of a binary system must once have been 
close to each other. The next step is the rupture of the parent neb- 
ula in the form of an hour-glass into two detached masses, as witness 
the great dumbell nebula (27 Messier Vulpeculz). Dr. T. J. See’s 
observations and ingenious theories have done much to develop this 
philosophy ot Dr. Darwin’s ; let us remember that conjecture is the 
parent of discovery and often the grandparent of truth. Future re- 
searches with the photographic plate, the spectroscope, and the teles- 
cope, and their results interpreted by skilful astronomers, will open to 
us yet marvellous vistas of observation ; like the Queen of Sheba 
we may yet have occasion to be startled with many sparkling gems 
of discovery and exclaim that the half was not even dreamed of. 
Tidal action has been in the mighty hands of the great Sculptor 
the instrument by which he has hewed out the outlines of our globe, 
working out new beauties, softening down harsh lines, and reducing 
her more and more fit for the habitation of man. Mother Earth 
sent forth her daughter Moon ages ago, and since then, obedient to 
Earth’s impulses, and never leaving her, she has with strong but 
gentle hands, moulded Earth’s plastic form into shapes and curves, 
and worked out with its wondrous friction coupled with Earth’s in- 
ternal forces these configurations of ocean and continent that are 
ncy wil ts And since Earth became in a sense solidified, the 
Moon has kept the oceans moving and heaving and health-giving, 
deftly shaping and rounding the fulness of her beauty. Many times 
