De 

NATURE 
[JULY 15, 1915 

pedance of the transmitting circuit at the instants 
when the current is naturally zero. Dots, dashes, 
and spaces are each sent by semi-waves of either sign, 
but of different amplitudes. The alternating current 
received may be read directly from the record made 
by a siphon recorder, or this current may be employed 
to operate a siphon Morse printer, by means of an 
adaptation of Muirhead’s gold-wire relay, or a Heurt- 
ley magnifier and a local wire relay. (3) The voltage 
stress along an Atlantic cable when an alternator is 
employed is shown, and the transmitting impedance 
of such a cable is computed as the frequency varies. 
(4) A special form of cable dynamo to operate at 
frequencies from 4 to 10 was used in the experiments 
described. (5) The fundamental principle is developed 
of never metallically “breaking ”’ the transmitter cir- 
cuit, which permits of greater accuracy in balancing 
the duplex bridge. 
EDINBURGH. 
Royal Society, June 21.—Prof. Hudson Beare, vice- 
president, in the chair.—Dr. A. Lauder and T. W. 
Fagan : The composition of mill as affected by increase 
in the amount of calcium phosphate in the rations of 
cows. In these experiments the amount of calcium 
phosphate added was gradually increased to 8 oz. per 
head per day. No increase in the amount of phos- 
phorus or of mineral matter in the milk could be 
detected, in agreement with the generally received 
opinion that within wide limits the composition of 
millk was little affected by the nature of the food fed 
to the cow.—J. Herbert Paul: A comparative study of 
the reflexes of autotomy. Self-amputation of limbs in 
the Decapod Crustacea is accomplished in various 
ways. Thus hermit crabs when removed from their 
shells usually respond to injury by plucking off the 
damaged limb with their claws. The “true” crabs 
possess a_ specialised mechanism by which the 
limb is weakened at the breaking plane, so 
that a very slight force can sever it. In 
lobsters, a special muscle, by violent  contrac- 
tion, weakens the limb along a groove in_ the 
third segment, and immediately the imprisoned limb 
is left in the grasp of the enemy. If the more highly 
developed mechanism is disorganised in certain species, 
the animal returns, as it were, to the wavs of its 
ancestors, and attempts to amputate the injured limb 
by more primitive methods.—Dr. M. Young : A contribu- 
tion to the study of the Scottish skull. The investiga- 
tion was based upon a study of more than 7oo skulls 
which have been for some years in the possession of 
the anatomical department of the University of Glas- 
gow. The greater number were collected by W. K. 
Hutton, lecturer in anatomy, Queen Margaret College, 
and were obtained during the excavation of an old 
Glasgow burying ground. The skulls are in the great 
majority of cases West Scottish skulls. They are 
more dolichocephalic than the average of Sir William 
Turner’s series of Scottish skulls, but resemble most 
closely those in this series which are derived from 
Renfrewshire. Comparison between the two series 
has been made by the ordinary method; and the Glas- 
gow collection has also been examined by modern bio- 
metrical methods, and the variability, as well as the 
correlation of the West Scottish skull as regards many 
of its dimensions and characters, have been determined 
and compared with those found in other series of 
skulls. One hundred specimens in the collection were 
divided in the medial sagittal plane, and from a study 
of the sectorial diagrams it appears that certain values 
of features which have been regarded hitherto as of 
morphological importance in different races fall within 
the range of variation shown by the large homo- 
geneous West Scottish series. The skulls are similar 
in type to the ‘‘Long Barrow” crania from the cham- 
NO. 2385, VOL. 95] 
’ 


bered caverns of Arran, described by Prof. Bryce, and 
the Whitechapel English series of crania described by 
Dr. Macdonnell. They are without doubt those of the 
descendants of the Iberian or Mediterranean stock or 
race who have remained in the West of Scotland and 
have been less influenced by the later brachycephalic 
type than has been the case in the east of Scotland. 
Their mean values represent only a type of Scottish 
skull, but this type perpetuated in comparative purity 
in the present collection is that which, modified by 
various factors, has resulted in the diverse cranial form 
seen in Scotland at the present day.—Dr. Ashworth and 
Dr. J. Ritchie: The morphology and development of 
the free-swimming sporosacs of the hydroid genus 
Dicoryne; with description of a new species. The 
sporosacs of D. parthenopeia closely resemble those of 
D. conferta, except that they have a single tentacle, 
and the female sporosac bears only one ovum. The 
oocytes are differentiated and grow in the ectoderm 
of a blastostyle in the position which the sporosac will 
ultimately occupy; there is no migration of oocytes. 
The sporosac does not exhibit during development any 
trace of medusoid structure; there is no evidence that 
this sporosac has undergone regression from the con- 
dition of a medusa or medusoid gonophore. The 
general structure of the colony of D. parthenopeia, the 
regenerative capacity of the stolon, the method of 
release of the sporosacs, and the early development of 
the egg are also described. 
Paris. 
Academy of Sciences, July 5.—M. Ed. Perrier in the 
chair.—M. Giller: Lightning and telegraph lines. An 
analysis of certain features common to all telegraph 
posts struck by lightning, and a suggestion for avoid- 
ing damage by the introduction of a spiral resistance 
possessing self-induction.—Henri Pénau: Cytology of 
the Bacillus verdunensis. This new species has been 
found in water at Verdun, and has some properties in 
common with the coli bacillus, from which, however, 
it can be separated. Details of various stages of 
growth are given.—M. Gard: A genus of Papilonacez, 
new for cyanogenesis.—Ed, Crauzel: The treatment of 
recent wounds by an expansible solution of iodine. 
The use of ether containing 5 per cent. of iodine in 
solution is suggested as offering advantages over the 
usual alcoholic tincture. It does not change in 
strength, and penetrates rapidly into wounds.—J. 
Cluzet: A simple method for the electrical examination 
of paralytics. The apparatus consists of a system of 
condensers, capacity from o-o1 to 12 microfarads, 
capable of utilising directly current from lighting 
mains. The use of the instrument in diagnosis is 
described.—A. Policard and A. Phélip: The first stages 
of the evolution of lesions in wounds caused by war 
projectiles, with some practical consequences. All 
fragments of clothing must be removed from the 
wound at the earliest possible moment. Too free use 
of antiseptics may diminish the defensive reaction of 
the tissues in the neighbourhood of the wound.—M. 
Billon-Daguerre: \ mode of producing thin sheets of 
liquids for sterilisation by ultra-violet light. 
Wasuincton, D.C. : 
National Academy of Sciences, presented to the 
Academy from April 15 to May 22.—C. G. Abbot, 
F. E. Fowle, and L. B. Aldrich ; Confirmatory experi- 
ments on the value of the solar-constant of radiation. 
Observations at Mt. Wilson from sunrise until ten 
o’cloclx, and records obtained by a recording pyrhelio- 
meter attached to sounding balloons rising to the 
altitude of 24 km. confirm the value of 1°93 calories 
per square centimetre per minute previously obtained 
for the radiant energy received by the earth from 
the sun.—T. H. Goodspeed and R. E. Clausen: Varia- 

