616
THE NEW ZEALAND GAZETTE.
of those Departments, and I now transmit to you the
substance of a Report by Dr. Buchanan, of the Privy
Council, which has been furnished to me by that
Department in reply to my inquiry, and which you
will find to contain an able and complete exposition
of the question.

Dr. Buchanan, as you are aware, is a distinguished
sanitary physician, and, as one of the Inspectors of
the Medical Department of the Privy Council, has
conducted a number of scientific investigations con-
nected with hygiène, his reports on which are well
known both here and abroad. The Earth Closet
System, of which Dr. Buchanan gives an account, has
been successfully introduced into Germany, and the
Report which I now enclose has been translated into
German, in the Deutsche Vierteljahrsctcrift Offentliche
Gesundsheitspflege of Varrenirapp.

I have received from the Duke of Argyll a mass
of reports and memoranda on the subject, the tenor
of which is such as to leave no doubt of the success
of the system, even when applied upon a large scale.
But as those papers are very voluminous, and as Dr.
Buchanan's report contains a recapitulation of their
substance, so far as the progress of experiment has
not rendered them obsolete, I do not think it would
be of advantage to swell the enclosures to this
Despatch with them.

The Dry Earth System has hitherto been used
chiefly in Public Institutions; but you will gather
from Dr. Buchanan's report that he conceives it to be
applicable to the sewage of whole towns, as indeed it
has been applied to some extent, and with success, in
Lancaster. In the event of its being applied on such
a scale, the disposal of the earth used in these closets
becomes a matter of considerable moment, with a
view both to its profitable employment in agriculture,
and to the effect of vegetation in finally disinfect-
ing it.

If the earth would be of commercial value in
your Colony as a manure, it may be hoped that pri-
vate enterprise will find the way to realize that value;
but, in any case, the public authorities will probably
be disposed to promote, so far as they have the
means, the adoption upon a large scale of an inven-
tion so beneficial to the health of the community.

I have, &c.,
KIMBERLEY.

The Officer Administering
the Government of New Zealand.

EXTRACT FROM A REPORT ON CERTAIN MEANS OF
PREVENTING EXCREMENT NUISANCES IN TOWNS
AND VILLAGES, BY DR. BUCHANAN.

IT is desirable to begin with a definition of the Dry
Earth System. It consists in the application, with
the greatest procurable detail, of dry earth to fresh
human excrement, and in the subsequent removal and
use of the mixture for agricultural purposes. In so
far as detailed application is not made, or as the
earth is not dry, or the excrement not fresh, or the
mixture otherwise dealt with, the Dry Earth System
is departed from. It is essential that this definition
should be kept in mind, as allegations respecting the
action of the dry earth system have been made from
the experience of places where the primary conditions
of the system have scarcely been attempted to be
fulfilled.

WORKING OF THE DRY EARTH SYSTEM.
The Earth Closet in General.

As regards the principle of the earth closet, the
evidence as to the powers of dry earth is unequivocal.
If about a pound and a half of suitable earth, carefully
dried, be thrown over a dejection, all smell from it is
forthwith removed; and if the same quantity be mixed
with half a pint of urine, the latter is absorbed. The
mixture of earth with stool and urine is not only
inoffensive when fresh, but remains so after keeping
for two or three months or longer.

The process which goes on in the mixture is
obviously one of disintegration and of some combina-
tion between the earth and the organic matter, as is
evidenced by the disappearance of stools and even of
paper among the other constituents of the compost.
But the absence of fætor from the mixture of earth
with stool or urine, even with prolonged keeping,
shows that decomposition in the ordinary sense does
not take place.

The Rev. H. Moule, to whose observations the
practical use of these facts is due, regards the process
which takes place in the mixture as consisting in a
change of the organic substances of excrement into
the state in which organic matter naturally exists in
fertile soil, in such a way that the animal refuse
becomes proximately available for the support of the
plant, without undergoing ultimate reduction into
simple salts and gases.

In order that that the described result shall be efficiently
brought about, the quantity and quality of the earth
have to be considered. With any quantity materially
less than a pound and a half to the average dejection
(unless some artificial means, not generally applic-
able, of mixing are had recourse to), a tendency to
wetness remains, and more or less fœtor results. If
much more earth is used, the proportionate agricul-
tural value of the product is lessened. The quality
of earth, as affecting its power of producing an
inoffensive compost with excrement, is of at least
equal importance with its quantity. Sand and gravel
have almost no power in this respect. Chalk has very
little. Clay stands very high in rank. Properly
dried it falls readily into a convenient powder, which
has great power of absorption and of preventing
offensive change. High in rank also is surface earth,
that which is loamy being preferable to any of peaty
character. One of the best of all earths is the brick
earth of the drift. Earths which already contain
some quantity of organic matter are very suitable.
Some one of these better sorts of earth may be readily
procured in most parts of England.

The mixture of excrement and earth appears to
become more intimate after a little time has elapsed;
for whereas the mixture when fresh will, if exposed to
heat or wet, enter into ordinary decomposition and
become fœtid, it may (if a proper proportion of good
earth have been used), after remaining a month or so
(during which time it gives off no offensive gases), be
exposed to wet and to any moderate degree of heat
without the production of any smell.

I have next to mention a circumstance, of the truth
of which I have complete evidence, both from the
statements of those who have used the system, and also
from my own observation, but which was at first
unexpected and surprising to me. It is, that the
mixture of excrement with earth, after being kept
awhile and then dried, has again the power which
the original earth possessed of absorbing and making
inoffensive any stools and urine to which it is applied.
This power is so marked that it has repeatedly been
alleged to me that the earth (especially of clay) acts
better a second time than the first; and I can answer
from my own observation that earth used three and
four times over, with drying at the proper stages,
will render excrement quite inoffensive. The limits
of this power do not appear to have been reached;
but, for experiment's sake, the earth has been
employed a dozen and more times over, when it must
have come to have more than half its bulk of excre-
ment, with the same result on the dejections as at
first, but with the other result of getting a manure
too strong for use by ordinary methods to the land.