March 17, 1870] 
NATURE 
507 
exceedingly plausible. I therefore did my best to point out its 
fallacy, partly with a yiew of convincing him, He replies, not 
by arguments, but by a personal attack on me, the acrimony of 
which I deplore but cannot explain, and by re-asserting his 
opinion as “a fact long accepted as beyond question. . . . by 
authorities too numerous to name.” In short, it appears to be 
“a fact” which the proverbial schoolboy ought to know ; but I 
am neyer more pleased than when the schoolboy with his universal 
knowledge is brought out against me. It is generally a sure sign 
that the assumed ‘‘fact” has no other foundation than that 
intelligent youth’s imagination. 
In the present case I say that if a man buys sewage he should 
buy it as he would any other manure, on the basis of a chemical 
analysis. I say that this is the ovZy safe and reliable basis on 
which to found a calculation of its money value. And I say that 
if a farmer puts so much money’s worth of manure into his land, 
he is simply a bungler if he does not get it out agam with ils 
proper increment of profit, whether he buries it in his land by 
means of a plough, or of a spade, or of water. Dr. Paul, on 
the other hand, says that if a man pays so much money for so 
much sewage because it contains a certain percentage of ammonia 
he will be ruined. Why? Because of the water. 
Of course we all know that water applied to certain crops in 
certain stages would spoil them; so would manure. If, there- 
fore, a farmer applies sewage under such conditions, he is a 
bungler. His skill, as a sewage farmer, is shown in so arranging 
his land and crops as never to injure but always to benefit them 
by the application of his sewage. This is simply a question of 
good versvs bad management. It is one to be decided on the 
farm and not in the laboratory, Incredible as it may appear to 
Dr. Paul, on taking a lease of the sewage of the town of Rom- 
ford, although bound, under penalty, to use it every day in the 
year, I stipulated for an additional dilution of the sewage to the 
extent of twenty gallons of water per head of the population fe 
diem, and this although I have not got the proportion of 
**twenty-five acres for every 100 persons,” as Dr. Paul says I 
recommend, but which I never recommended, and should be the 
first to condemn, 
Having defended my opinion, I will now, with your permis- 
sion, defend my character. Dr. Paul regrets that I should 
“declare myself a partisan of one particular solution of the 
town-refuse problem.” It may be that he has so recently com- 
menced the study of this large question that he has, as yet, formed 
no opinion upon it except that by irrigation the value of the 
manure cannot be recovered ; but I have laboured at it for many 
years, and it is not possible that in those years I should not have 
formed some very distinct opinions. Will any one else regret 
that I should ‘* declare” what those opinions are? I think not; 
and I think that such a declaration is straightforward and honest, 
though why Dr. Paul should affect to think that I have made it 
now for the first time I cannot say. My views on this sub- 
ject have been publicly expressed for many years, and have 
been so expressed in his presence. Dr. Paul complains that 
I desire “‘the promotion of a project at any price.” I do, 
I desire to see sewage utilised all oyer the country, and by irni- 
gation, if possible, because I believe it is the right thing, and I 
am gratified to find that my views are in exact accord with those 
expressed in the unusually careful and able report just published 
by the Royal Commission on Pollution of Rivers. But when I 
joined the Committee of the British Association on Sewage, I 
at once suggested that the scope of their inquiry should be 
enlarged so as to include a full investigation into every proposal 
for the utilisation of sewage which presented any appearance of 
practicability. I also suggested a source from which the neces- 
sary funds might be obtained. My suggestions were approved 
both by the Committee and by the Council of the Association, 
the funds have been in great part obtained, and the inquiry is 
about to be prosecuted. Whether Dr. Paul is justified in the per- 
sonal atlack he makes upon me, I will therefore leave to the 
judgment of your readers. 
I will merely add, as regards my opinions, that they were 
condemned in the most unqualified and unmeasured language by 
Baron Liebig five years ago; but I have lived to prove Liebig 
mistaken in this instance, and, on the practical farming part of 
the question, I think I may claim to be a very much better 
authority than Dr. Paul. At all events, as the German philo- 
sopher said of the author of the Epistle to the Corinthians, ‘‘I 
do not agree with your Dr. Paulus,” and I have yet to learn that 
such a disagreement involves the breach of any law, human or 
divine, although Dr. Paul is evidently firmly convinced that 
while #e has an undoubted right to express ‘‘a foregone con- 
clusion,” such an expression on #zy part is a sign of great moral 
depravity. This is a common form of superstition, but it is 
scarcely scientific, and seldom adds much weight to a man’s 
opinions. W. Hore 
Parsloes, March 6 
Transactions of Scientific Bodies 
T WISH it were possible to induce our learned societies to be 
a little more liberal ; it should be their aim to spread knowledge, 
not make it a luxury for the wealthy. I happen to wish to 
read a paper by Professor Tait on “ Rotation,” published in the 
Transactions of the Royal Society. of Edinburgh. The only 
libraries I have access to are those of the British Museum and 
London Institution. At the Museum there is no volume of the 
*“Transactions ” later than 1864; at the London Institution no 
volume later than 1862 ; so that if I persevere in my intention of 
reading the paper, I must buy the volume containing it, for which 
I must pay 2/. 2s.—that is, I must buy thirteen papers I don’t 
want in order to be able to read one which I do want: these 
include one on the temperature of newly-born children, and 
another on tetanus in cold-blooded animals. 
All papers should be published separately ; this would lead to 
a much wider diffusion of them, and the Societies would benefit 
by their increased sale. 
London, March 7 G, 
Sir. W. Thomson and Geological Time. 
TuE North British Review, for July last, thoroughly exposes 
the inaccuracy of the quotation from Prof. Thomson, referred to 
by your correspondent G.I., in its article deyoted to the con- 
sideration of Geological Time. io 134 
Your correspondent G.H. will find in one of Thomson's 
papers something very like the assertion ‘‘that there was a time 
when the earth rotated too swiftly for the existence of life,” but 
expressed in a manner at once more precise and less pleonastic. 
“The existence of life” reminds me of a phrase which I heard a 
few days ago from a female beggar; she lamented that her 
husband had ‘fallen into habits that are habitual.’’ Well; the 
required reference is the paper ‘On Geological Time,” in the 
Transactions of the Geological Society of Glasgow, vol. ili. 
Part I. pp. 15 and 16 ($$ 19 and 20). A thousand million years 
ago, says Thomson, ‘‘there must have been more centrifugal 
force at the equator due to rotation than now, in the proportion 
of 64 to 49. ... If the earth rotated seventeen times faster, 
bodies would fly off at the equator. If you go back ten 
thousand million years ago—which, I believe, will not satisfy 
some geologists—the earth must have been rotating more than 
twice as fast as at present—and if it had been solid then [which 
he thinks improbable], it must be now something totally different 
from what it was.” Such a state of things he seems to consider 
inconsistent with any organic life such as we know of. Surely 
the connection of this question with the argument from retard- 
ation by tidal friction is too plain to need exposition. 
Ilford, March 11 C, M, INGLEBY 
How large seems the Moon ? 
ReapinG Mr. R. A. Proctor’s communication under the above 
heading in NATURE of March 3rd, reminds me of an experiment 
I tried some time ago. I imagined I should get all sorts of 
answers to the question, varying from ‘‘a fourpenny-piece” 
upwards, without any particular size being more frequently 
pitched on than any other. I did not collect more than about 
twenty or thirty replies, but they were sufficient to show that, 
contrary to my expectation, exe 4o twe feet was assigned more 
frequently than other sizes. Mr. Proctor says the estimate of a 
foot in diameter assigns a distance of 115 feet tothe moon. If 
he were to try to convince the observer of the soundness of this 
deduction, the latter would probably meet him with vehement 
reiteration that he only means the moon /ogés a foot large. It 
seems to me fairer to say that such a man thinks a two-foot rule 
115 feet off, a fit and proper measure for celestial objects. I 
think many, who are aware of the futility of attempting to convey 
their ideas to other minds by these comparisons, yet involuntarily 
make them in their own. I am conscious of a lurking idea that 
the moon is more like a fourpenny-piece in size than anything 
else. The question is, what is the cause cf the ‘‘ personal 
equation” which determines for each indiyidual the distance of 
