The ever-shifting ground of scientific progress, p. 203--Solar and
telluric problems, p. 205--Mayer's explanation of the continued heat
of the sun, p. 206--Helmholtz's suggestion as to the explanation, p.
207--The estimate of the heat-giving life of the sun by Lord Kelvin
and Professor Tait, p. 208--Lockyer's suggestion that the chemical
combination of elements might account for the sun's heat, p.
209--Computations as to the age of the earth's crust, p. 210--Lord
Kelvin's computation of the rigidity of the telluric structure, p.
211--Estimates of the future life of the earth, p. 212--Physical
problems, p. 213--Attempts to explain the power of gravitation,
p. 214--The theory of Le Sage, p. 214--Speculations based upon the
hypothesis of the vortex atom, p. 216--Lord Kelvin's estimate of the
vortex theory, p. 217--Attempted explanation of the affinity of
atoms, p. 217--Solubility, as explained by Ostwald and Mendeleef, p.
218--Professor Van 't Hoof's studies of the space relations of atoms, p.
219--Life problems, p. 220--Question as to living forms on other worlds
besides our own, p. 21 x--The question of the "spontaneous generation"
of living protoplasm, p. 222--The question of the evolution from
non-vital to vital matter, p. 223--The possibility of producing organic
matter from inorganic in the laboratory, p. 224--Questions as to
the structure of the cell, p. 225--Van Beneden's discovery of the
centrosome, p. 226--Some problems of anthropology, p. 227.