JUNE 5, 1902 | 
NATURE 
137 
( Journal of the Anthropological Institute, vol. xxxi. p. 167), 
states that in New Britain the local wizard trephines witha piece 
of shell or witha flake of obsidian in cases of fracture caused by 
a sling stone. This operation is described ; the number of deaths 
is about 20 per cent., most of these resulting from the first 
injury and not from any complication after the operation. Com- 
plete recovery takes place in two or three weeks’ time. In New 
Treland the operation is performed, not only in the case of fracture, 
but where there is epilepsy and certain forms of insanity as the 
result of pressure on the brain. After trephining has been 
performed, there is frequent partial temporary paralysis, which 
almost invariably passes away. Idiotcy is an occasional result 
also. But the natives affirm that while the cures of insanity 
and epilepsy are many, the instances where either malady super- 
venes after the operation are exceedingly few. Dr. Victor 
Horsley’s discussion of this paper lends it additional interest. 
Onz of the latest departures of the experimental psychologist 
consists in prodding people witha pointed instrument when they 
are asleep to find out how much excitation is required before they 
begin to move, and how much it takes to wake them up. This 
method is embodied ina paper on ‘‘ Experimental Investiga- 
tions on the Depth of Sleep,” by Drs. Sante de Sanctis and 
U. Neyroz, of Rome, a translation of which is given in the 
Psychological Review for May. The instrument employed is 
called a Griessbach ethesiometer (made by Brandli, of Basle), 
and may be used with either a sharp or blunt point. It 
measures the stimulus necessary to induce subconscious 
reaction, and that applied at the waking point. Four normal 
subjects, all relatives of the writer of the paper, were experi- 
mented on for about six consecutive months, and afterwards 
five subjects, mostly epileptic, were operated on, and from the 
results obtained curves were drawn showing the relative depth 
of sleep, as measured by the stimuli required, after the subject 
had been allowed to sleep for various lengths of time. The 
curves are all of zigzag form, and the experiments may per- 
haps suggest a practical application in the case of subjects who 
find it hard to wake in the morning, and who may overcome 
the difficulty by timing their sleep so that the waking point 
is ata minimum when they wish to rise. 
In the Report of the Marlborough College Natural History 
Society for 1901, Mr. S. B. Dixon gives an account of the 
recent important discovery of Palzolithic flint implements at 
Knowle, near Savernake Forest. The state of the Society 
appears to be flourishing, the entomological section showing a 
specially good record of work. The report is illustrated by 
some excellent reproductions from photographs of local scenery. 
ACCORDING to the Berlin correspondent of the Z%zes, an 
international agreement for the protection of birds useful to 
agriculture was signed at Paris on March 19, the contracting 
parties being Belgium, France, Greece, Lichtenstein, Luxem- 
burg, Monaco, Austria-Hungary, Portugal, Sweden, Switzerland 
and Spain. Certain insectivorous species and others scheduled 
as being specially useful to agriculture are to receive uncondi- 
tional protection, the destruction of the birds themselves, or of 
their nests and eggs, being prohibited at all seasons. It is 
noticeable that Italy, where numbers of useful birds are annually 
killed during migration, does not appear among the signatories. 
IN the introductory comments to the second (May) number 
of the Fre/d Naturalists Quarterly, the editor discusses the 
proper sphere of work for local natural history societies. The 
importance of taking cognisance of all subjects connected with 
local biology is strongly urged, as the specialists are sure to 
look after their own interests, and will, when necessary, insti- 
tute sections devoted to their own favourite subjects. ‘‘ The 
great justification of a field club ought to be that it is doing 
NO. 1701, VOL. 66 ] 
work that is otherwise neglected. There is not an area of ten 
miles square in this country but what offers some subject of 
investigation.” Several of the articles in this number deal with 
the habits and movements of animals in spring, and the illus- 
trations include some interesting photographs of nests and eggs. 
WE have received the “‘ Catalogue of the Educational Collec- 
tion of Minerals belonging to the West Ham Municipal 
Technical Institute,” compiled by Dr. H. A. Auden. Froma 
high scientific standpoint the classification here adopted of 
minerals, according to electronegative constituents, will no 
doubt meet with the approval of the learned. Under this 
arrangement, zincite, corundum and hematite (as simple 
oxides) follow one another; and the same is the case with 
anhydrous carbonates, such as aragonite, witherite, strontianite 
and cerussite. For purposes of technical education a practical 
grouping would appear more desirable. The author’s object is, 
however, to illustrate the systematic grouping of mineral 
specimens, and in the ‘‘addenda” he enumerates the prin- 
cipal metals and ores, jewels and other minerals of industrial 
importance. An index would have added to the value of this 
useful work. 
A NEw general method for the synthesis of fatty aldehydes 
is described by MM. L. Bouveault and A. Wahl in the current 
number of the Comptes rendus. It was shown by Henry some 
time since that aldehydes of the fatty series could be readily 
condensed with nitromethane to form addition products, which 
the authors have now found to readily lose water to zinc chloride 
under suitable conditions, giving nitro-derivatives of substituted 
ethylenes. These are readily reduced by zinc and acetic acid 
to oximes, from which the aldehyde can be obtained without 
difficulty. The method has been applied by MM. Bouveault 
and Wahl to the synthesis of isobutylacetic aldehyde from the 
product of condensation of isovaleral with nitromethane, and of 
caprylic aldehyde from cenanthol. 
SINCE the discovery of the remarkable compound of hydrogen 
and nitrogen known as hydrazoic acid, numerous modes of 
preparing it have been worked out, mostly through the use of 
somewhat complicated organic compounds. The only purely 
inorganic syntheses of this acid are those of Wislicenus from 
sodium amide and nitrous oxide and of Tanatar from hydrazine 
and nitrogen chloride. Tanatar now describes in the current 
number of the erzchtfe another elegant synthesis of this com- 
pound. A mixture of hydrazine sulphate and hydroxylamine 
hydrochloride is treated in acid solution with an oxidising agent 
and distilled, when hydrazoic acid passes over with the distillate. 
Hydrogen peroxide and chromic acid appear to give the best 
yields, which in no case exceed 30 per cent. of the theoretical 
amounts. Dihydroxylamine is probably the first product of 
oxidation, which then condenses with the hydrazine and is 
further oxidised to N,H. 
Dr. M. BIAt has recently carried out some interesting experi- 
ments on the antiseptic properties of dilute solutions of acids, 
details of which are given in the last number of the Zeztschraft 
fiir phystkalische Chemie. The observations were carried out 
with yeast cells, measurements of the retarding action of 
different acids on the development of the cells being made by 
observing the amount of carbon dioxide liberated from a solution 
of grape sugar. It is found that the concentrations of the solu- 
tions, which are just sufficient to check completely the develop- 
ment of the cells, are much smaller in the case of the strong 
acids like hydrochloric and sulphuric acids than in the case of 
weak acids such as acetic and butyric acids. The results, in fact, 
lead the author to conclude that the antiseptic power is essen- 
tially determined by the hydrogen ion which is contained in the 
acid solutions, and the electrolytic dissociation theory is able 
