NOVEMBER 30, 1916] 
48°5 per cent. of K,O, and kainit, a mixture of the 
chlorides and sulphites of potassium, magnesium, 
and sodium, containing on an .average 12 per 
cent. of K,O. Against these, a mica schist with 
only 3 per cent. of K,O does not look very pro- 
mising at first sight, and nothing but well-con- 
ducted vegetation experiments will show exactly 
what value the mineral does possess. Of course, 
if the technical chemist can find some easy way of 
making the sulphate or chloride, the whole aspect 
of the problem changes. Dr. Voelcker has ex- 
perimented at Woburn since rort with various 
potassic minerals, felspars, phonolite, granite, etc., 
to see if any of them possessed fertilising value, 
but so far the experiments have been without 
success. _ There is no experimental foundation for 
the suggestion sometimes made that these minerals 
might prove useful on poor soils by the slow libera- 
tion of potash. As a matter of fact, potash is 
most needed by plants on light, dry soils, and in 
these the decomposition of a complex silicate could 
scarcely be expected to proceed rapidly. 
NOTES. 
Tue death of the Rt. Hon. Charles Booth, F.R.S., in 
his seventy-seventh year, is a loss to the community of 
a munificent and judicious philanthropist, a pioneer in 
statistical and sociological work, a writer and speaker 
of force and attraction, and a sympathetic and prac- 
tical economist. He published in 1889 the first volume 
of his series of studies of ‘Life and Labour of the 
People,” a work which (as the Times truly says) “for 
nearly a generation profoundly affected public opinion 
on social questions.” His method was to employ 
trained investigators, who should ascertain the precise 
facts about the means of living and the general con- 
ditions of labour in each part of the district under 
consideration, and to group the results into classes, 
graduated according to the resources possessed and 
the manner in which those resources were applied. 
The task occupied him seventeen years, and called for 
an elaborate organisation and a large expenditure of 
time and money. His services to statistical science 
were recognised by the award by the Royal Statistical 
Society of its gold medal in 1892, by his election to 
the presidency of that society from 1892 to 1894, and 
by the fellowship of the Royal Society. His services 
to the public were recognised by the coveted honour 
of a summons to the Privy Council, and by honorary 
degrees from the universities of Oxford, Cambridge, 
and Liverpool. He was an original member of the 
Sociological Society, and presided at two meetings 
when Prof. Geddes developed his views on civics. He 
advocated a scheme of universal non-contributory pen- 
sions, and when he was asked to help Sir Edward 
Hamilton’s Committee on that subject he readily con- 
sented, and attended a meeting of that committee, 
giving advice which was found of great practical 
value. 
Sir Hiram S. Maxi, one of our greatest inventors, 
died on November 24, at his home at Streatham, after 
a short illness. Born in 1840, in the State of Maine, 
he had a childhood and youth of hard work, like the 
majority of voung Americans of that time. In his 
autobiography he recounts with pride how he picked 
up many trades and became skilful in the use of tools. 
Everything gave him occasion for thoughf and inven- 
tion, and it was of his early inventions that he was 
proudest. Before the age of forty he invented mouse- 
NO. 2457, VOL. 98] 
NATURE 
253 
traps, gas machines, fire sprinklers, a steam-trap, loco- 
motive headlights, electric lights, dynamo machines, 
and many other things. It is by the first automatic 
gun—the Maxim—a gun with a single barrel which 
discharged more than 600 ordinary rifle shots per 
minute, exhibited thirty-two years ago, that he is best 
known to the general public. For the next twenty 
years his time was mainly taken up in developing auto- 
matic guns of much greater size, and these are now 
used by all the nations. He had a good working know- 
ledge of physics and chemistry. He made discoveries 
about explosives, and seems to have been the first 
inventor of a smokeless gunpowder. He seems also to 
have been the first to see clearly the principle on 
which aeroplanes are worked, and he spent a great 
deal of money in finding out the horizontal speed 
required to give to inclined planes a definite amount of 
lifting power. His difficulty lay in the great weight 
of the necessary steam-engine and boiler. The later 
invention of the petrol engine easily made the aero- 
plane a real flight machine. He made his permanent 
home in England in r882, and became a British sub- 
ject. He was knighted in r901. A review of his 
autobiography will be found in Nature of April 22, 
Ig15. Scientific men, engineers, and inventors used 
all to start as amateurs; Maxim was nearly the last 
of these men of great originality. It will be interest- 
ing for our successors to notice whether the more 
orthodox training now in vogue tends better to develop 
originality or to destroy it. 
Tue second annual report of the Medical Research 
Committee, National Health Insurance, has just been 
issued, and deals with the year ending September 30, 
1916. In the introduction it is stated that the schemes 
for medical research in special directions, framed 
originally with a view to peace conditions, have for 
the greater part been suspended, and almost the whole 
of the available funds and scientific resources have 
been applied to the solution of medical questions of 
immediate national urgency in war-time. The sum- 
mary of research work carried out is divided into three 
sections—that of the Central Research Institute, 
Mount Vernon Building, Hampstead, and affiliated 
laboratories, pre-war schemes for research, and work 
in connection with the war. In the department of 
biochemistry much work has been done on the treat- 
ment of amoebic dysentery with emetine, and as an 
outcome a double iodide of emetine and bismuth has 
been ‘introduced by Dr. Dale, and appears to be a 
valuable drug in the treatment of carriers. Investiga- 
tions are also in progress by Dr. Barger and Dr. 
Ewins on organic arsenic compounds with a view to 
improvement of such remedies as atoxyl and _ sal- 
varsan. Dr. Leonard Hill and his staff have carried 
out investigations on the hygiene of munition fac- 
tories, on dangerous dusts and vapours, and on poison 
gases. Several pre-war researches on tuberculosis 
have been continued, and rickets, diabetes, diseases of 
the heart, anaphylaxis, and the sterilisation and con- 
tamination of milk are being investigated at several 
centres. As regards work in connection with the war, 
the Army medical statistics are being compiled by the 
committee at their statistical department under the 
direction of Dr. Brownlee. The treatment of infected 
wounds and the study of antiseptics are being carried 
out by the staff of the bacteriological department under 
the direction of Sir Almroth Wright. Dr. Dakin 
devised his antiseptic solution of sodium hypochlorite, 
and as a result of his work on this substance and in 
collaboration with Prof. Cohen introduced  chloro- 
amine T (toluene sodium sulphochloroamide), a new 
and potent antiseptic. Typhoid, paratyphoid, and 
dysentery infections. trench nephritis, cerebro-spinal 
fever, and disorders of the soldier’s heart are a few of 
