160 Maclure’s Letters. 
ed by the mutation of names introduced into theories, by 
the mixture and confusion of the three classes of Neptunian 
rocks ; some denominating secondary, what | termed transi- 
tion, and calling secondary a great part of what I call allu- 
vial. It is probable that the whole of those three great 
classes of Neptunian rocks was in the state of alluvial, before 
cement, affinity, attraction, or some other agent that nature 
may have employed to bring them into their present state, 
had consolidated them. 
I have never observed any extensive similarity in alluvial 
or diluvial (as it is the fashion of the day to call them) for- 
mations, but have rather remarked that every alluvial basin 
seems to have arisen from the situation of rocks in its Vi- 
cinity. 
The strong appetite which all animals have for licking 
salt, nitre, &c. found in most caves, naturally accounts for 
their bones being deposited there.” 
Improvements in Education—Infant Schools—Mechanical 
 Institutions—Cheap Publications—Mr. Phiquepal—Mr. 
Owen, &c. 
I have been much gratified with the progress of civiliza- 
tion, in all those parts of the British dominions which I have 
lately visited, and anticipate much pleasure in finding still 
greater improvements, both moral and physical with you, 
for there were only two things worth our imitating, viz- 
Infant Schools,’ Mechanical Institutions for teaching the 
oung men and apprentices the application of the sciences 
to the useful arts, and their cheap periodical publications 
for the industrious productive classes. These are sold at 
from 1d. to 3d. per.No., of one sheet of letter press, and 
they teem from the press every week, in editions of 100,000 
at a time, with more common sense, and useful information, 
than would have been found circulating 50 years ago in the 
most highly cultivated and scientific societies. Infant 
Schools are an excellent improvement, and a great benefit 
to society, and that even although they do not here learn 
them any thing suitable to their years, or the utility of which 
can possibly be understood by the children; but the congre- 
gating of them together in schools of 2 or 300, learns ob- 
servers how much can be done with children, and at how 
