494 
NATURE 
[JULY 1, 29215 

August; fresh manure as added is to be treated with 
ferric sulphate. 
In regard to blow-flies, M. Roubaud discusses means 
of preventing access of flies to dead bodies, and the dis- 
infection of corpses. In the first he states that heavy 
tar oil is to be used, as it preserves animal tissues 
when to per cent. cresyl, chloride of lime, formol, millx 
of lime, and 5 per cent. phenol fail to do so. Ferric 
sulphate is to be used as a protective covering, either 
powdered on or applied as 10 to 20 per cent. solution. 
The salt forms stable compounds with the tissues 
which cannot be attacked by flies, and the solution 
kills eggs and larva; the three substances required 
at the front then are ferric sulphate, heavy tar oil, and 
cresol. 
Some of the author’s statements, which are given 
without proofs, cannot be unreservedly endorsed; for 
example, it is practically certain that a dead horse 
powdered with ferric sulphate will still breed innu- 
merable flies unless it is periodically treated. No 
superficial treatment will clear a superficially dry 
manure heap of maggots; only a vapour treatment 
applied in liquid form. Also, a Io per cent. solution 
of ferric sulphate is a very expensive dressing unless 
the substance is available in enormous amount; and 
one of the difficulties of the front is the transport of 
material. Concentrated treatments are required if 
possible, not 1o per cent. treatments at great bulk. 
The problem of dealing with flies is very difficult, 
and is receiving much attention. One aspect is being 
carefully dealt with in this country, and the results 
will be available very shortly. This is the question 
of the treatment of the great aggregation of stable 
manure. The War Office have apparently accepted 
the American view of the value of borax; already a 
treatment with volatile liquid at a third of the present 
cost of borax has been found, which is satisfactory in 
that it spreads in the manure heaps and is not simply 
a superficial treatment; and it does not affect the 
value of the manure for horticultural purposes. Plants 
will stand very strong applications of volatile organic 
compounds, far stronger than are required to kill fly 
maggots, but which compounds are the best has yet to 
be determined. 

AIR POLLUTION. 
HE Air Pollution Advisory Board of the Sanitary 
Committee of the Corporation of Manchester 
has recently issued its first report. We are told that 
this Board came into existence two years ago as the 
result of a memorial presented to the Corporation by 
members of various scientific and other societies in 
the city with the object of examining the latest and 
best methods -of eliminating the smoke evil and of 
diffusing information on the subject. 
The Board consists of representatives of various 
committees of the Corporation, distinguished men of 
science, and influential members of numerous public 
bodies. It is divided into four sections, namely, the 
chemical, statistical, administrative, and engineering 
sub-committees. This is not the first occasion on 
which the public spirit of Manchester citizens has 
been inspired by the smoke nuisance and exercised 
itself in an attempt to suppress it. In 1891 a com- 
mittee of the town gardening section of the Man- 
chester Sanitary Society issued a report on some of 
the evils of smoke affecting vegetation and the amount 
of daylight; and in 1895 a ‘“‘committee for testing 
smoke-preventing appliances”? published a voluminous 
and comprehensive report on the various forms of 
apparatus used in steam boilers which were alleged 
to diminish or remove smoke. 
What the ultimate fate of these two committees was, 
NO. 2383, VOL. 95] 



the writer is unable to say; but though their activi- 
ties ceased, there is no doubt that they stimulated an 
interest in the subject which led not only to the 
formation of the present Board, but had the effect of 
inducing other municipalities to adopt a similar action. 
Work of the same character is now being carried on 
in fifteen other cities. This growing interest which 
has spread out from Manchester in ever-widening 
circles also led to the formation of a Local Govern- 
ment Board Committee on Smoke Abatement, which 
held numerous meetings in the first half of last year. 
The present report deals: mainly with the amount, 
nature, and extent of air pollution by smoke. The 
methods, which need not be described in detail, are 
based upon previous investigations of this character, 
and the results are not essentially different from 
those already recorded by other observers. 
Valuable as the information is as indicating the 
extent of atmospheric contamination (which is 4s 
injurious as it is wasteful and unnecessary) and in 
keeping public interest alive to the importance of the 
economic use of fuel, the accumulation of statistics 
of a nature already well authenticated will not of 
itself bring about any radical reform. 
We are glad to see, therefore, that the Board has 
in contemplation the study of all domestic coal-con- ~ 
suming grates and their efficiency, and an extensive 
propaganda by pamphlets, lectures, and exhibitions 
among builders and tenants in relation to domestic 
heating by coal, coke, gas, and electricity. Although 
a good deal of pioneer work has been done in this 
direction by various smoke abatement societies, it is 
just one of the subjects on which the views of the 
community are so firmly welded to the past that un- 
remitting agitation is necessary before the deeply- 
rooted tradition in the efficacy of the old-fashioned 
coal fire can be loosened. When this worl is com- 
plete, the time will be ripe for the consideration of 
more drastic measures of smoke abatement, and 
there is no doubt that had not the advent of the war 
postponed the deliberations of the Smoke Abatement 
Committee of the Local Government Board, the report 
of that committee would have greatly strengthened 
the hands of the municipalities in any future legisla- 
tion which they may have in view. 
In conclusion, we can only congratulate the Man- 
chester Sanitary Committee on the scientific way in 
which it has set about steadily accumulating evidence 
and wish it a full measure of success in achieving its 
ultimate object. BSG: 

RADIATIONS FROM EXPLODING ATOMS.1 
T is now well established that the radio-active sub- 
stances are undergoing spontaneous transforma- 
tion, and that their characteristic radiations—the -a, 
8, and y rays—accompany the actual disintegration of 
the atoms. The transformation of each atom results 
from an atomic explosion of an exceedingly violent 
character, and in general results in a liberation of 
energy many million times greater than from an equal 
mass of matter in the most vigorous chemical 
reaction. 
In the majority of cases the atomic explosion is 
accompanied by the expulsion of an actual atom of 
matter—an a particle—with a very high speed. 
It is known that the a particle is an atom of 
helium which carries two unit positive charges, and 
which leaves the atom with a velocity of about 10,000 
miles per second. In some transformations no a 
particle is ejected, but its place is taken by a swift 
8 particle or electron. These 8 rays carry with them 
1 Discourse delivered at the Royal Institution on Friday, June 4, by 
Sir Ernest Ruther‘ord, F.R.S, 

