NOTES. 
51 
antagonism of Individuation and Genesis ensures the final 
attainment of the highest form of maintenance of race—the 
greatest amount of life possible, and the fewest number of 
births and deaths. Fertility has brought about civilisation, 
civilisation will diminish fertility and destroy its excess. 
From the beginning pressure of population has been the 
cause of progress. It produced the original diffusion of the 
race, it compelled man to take to agriculture, it forced men 
into the social state and developed the social sentiments, it 
has stimulated us to increased skill and intelligence, and it is 
daily thrusting us into more mutually-dependent relation¬ 
ships, and, after having caused the due peopling of the globe, 
and the raising of all its habitable parts into the highest 
state of culture, and developed the intellect into complete 
competency for its work, and the feelings into complete 
fitness for social life, it must gradually finish its work and 
bring itself to an end. Evolution is, in fact, an advance 
towards equilibrium. 
He concludes by observing that the final result is that 
“in approaching an equilibrium between his nature and the 
ever varying circumstances of his inorganic environment, 
and in approaching an equilibrium between his nature and 
all the requirements of the social state, man is at the same 
time approaching that lowest limit of fertility at which the 
equilibrium of population is maintained by the addition of as 
many infants as there are subtractions by deaths in old age. 
Changes numerical, social, organic must by their mutual 
influences work unceasingly towards a state of harmony—a 
state in which each of the factors is just equal to its work.” 
[These Expositions of Herbert Spencer’s “ Principles of 
Biology” are now concluded. They commenced in 
vol. Vil., p. 35.] 
ft 0 t c s. 
Hoar Frost in January, 1888.— Fact and Theory. —Having occasion 
yesterday at noon (12th January) to make an observation with an 
anemometer in the mouth of a rectangular wooden pipe, fixed vertically 
into the ground and communicating ventilation to some underground 
excavations of a fire-clay mine near here; it was necessary to remove 
a square of wire gauze (whose meshes were inch square), which 
had been nailed over the mouth of the said pipe to protect it. Now, 
covering the upper surface of this wire gauze was a beautifully evenly- 
formed layer or cake of cellular ice or hoar frost, very much resembling 
the comb of the honey bee, only the cells were four-sided instead of 
