nous districts;--irrigating tracts of desert in
the torrid zone;--breaking up, and thus rendering capable of quicker
fusion, edges of ice in the northern and southern Arctic seas, &c., so
rendering parts of the earth habitable which hitherto have been
lifeless, are to be studied under this head.

The value of instruments is, secondarily, in their aid to abstract
sciences. The degree in which the multiplication of such instruments
should be encouraged, so as to make them, if large, easy of access to
numbers (as costly telescopes), or so cheap as that they might, in a
serviceable form, become a common part of the furniture of households,
is to be considered under this head.[12]

18. (iii.) Food, medicine, and articles of luxury. Under this head we
shall have to examine the possible methods of obtaining pure food in
such security and equality of supply as to avoid both waste and famine:
then the economy of medicine and just range of sanitary law: finally the
economy of luxury, partly an aesthetic and partly an ethical question.

19. (iv.) Books. The value of these consists,

First, in their power of preserving and communicating the knowledge of
facts.

Secondly, in their power of exciting vital or noble emotion and
intellectual action. They have also their corresponding negative powers
of disguising and effacing the memory of facts, and killing the noble
emotions, or exciting base ones. Under these two heads we have to
consider the economical and educational value, positive and negative, of
literature;--the means of producing and educating good authors, and the
means and advisability of rendering good books generally accessible, and
directing the reader's choice to them.

20. (v.) Works of art. The value of these is of the same nature as that
of books; but the laws of their production and possible modes of
distribution are very different, and require separate examination.

21. II.--MONEY. Under this head, we shall have to examine the laws of
currency and exchange; of which I will note here the first principles.

Money has been inaccurately spoken of as merely a means of exchange. But
it is far more than this. It is a documentary expression of legal claim.
It is not wealth, but a documentary claim to wealth, being the sign of
the relative quantities of it, or of the labour producing it, to which,
at a given time, persons, or societies, are entitled.

If all the money in the world, notes and gold, were destroyed