380 
NALECRE. 
[FEBRUARY 18, 1904 
when a very powerful Nernst lamp was employed. More- 
over, this sustained gaze is always accompanied by great 
fatigue, for reasons already adduced, and especially so in 
observing a very feebly luminous surface of small area in 
a dark room. The sustained gaze at small bright objects, 
as is well known, is, in fact, the most effectual way of 
inducing hypnotic sleep. 
But although one cannot imitate all M. Blondlot’s ex- 
periments by purely subjective perceptual processes without 
employing some source of illumination, I have thought it 
advisable to direct attention to these more recent physio- 
logical discoveries, the more so as M. Blondlot pays no atten- 
tion to them in any of his publications, and does not state 
with what visual apparatus one ought to observe, nor does 
he give warning of the illusions one may fall into in carry- 
ing out his experiments. But the foregoing statements will 
at least serve to remind all those who take the trouble to 
repeat M. Blondlot’s experiments that in vision in the dark 
changes in brightness, form and colour may arise from a 
purely subjective source. These purely subjective changes, 
however, do not depend upon any optical illusion, but, like 
the ‘‘ shadow-like ’’ appearances of the ‘‘ grey glow’ and 
the ‘‘ red glow,’’ are brought into existence by the com- 
petition between the two elementary structures of the visual 
organ, and correspond to objective processes in the retina. 
As soon as the phenomena observed by M. Blondlot shall 
have been incontestably proved by means of objective in- 
struments of precision, these few remarks on the n-rays will 
be only of secondary importance. 
UNIVERSITY AND EDUCATIONAL 
INTELLIGENCE. 
CAMBRIDGE.—At a meeting held at The Museums, Cam- 
bridge, on February 8, Prof. Newton, F.R.S., being in the 
chair, it was decided to take steps to perpetuate the memory 
of the late Mr. J. S. Budgett. Since his return from his 
last expedition to Africa, Mr. Budgett had made some im- 
portant observations on the material collected by him, but 
a large part of the valuable material which he gave his 
life to obtain was necessarily untouched by him. It is pro- 
posed that this should be worked out by some of his friends, 
and the results published, with the observations and draw- 
ings which he had himself made. The work would be 
edited by Prof. J. Graham Kerr, and suitably illustrated. 
It is also proposed, if the funds available are sufficient, to 
add to the volume a reprint of all Mr. Budgett’s former 
writings, so that the volume will become a memorial of his 
life’s work. Subscriptions towards the cost of preparing 
this volume should be sent to Mr. A. E. Shipley, Christ’s 
College, Cambridge. 
A VERBATIM report of the conference of teachers, held 
under the auspices of the London Technical Education 
Board on January 7-9, appears in the London Technical 
Education Gazette—the official circular of the Board—for 
January and February. 
Ar a joint meeting of the academical and university 
councils of Paris, some interesting remarks were made by 
M. Liard arising out of the recent changes according to 
which professors of secondary education were last year, 
for the first time, allowed to sit on juries for the 
baccalaureate. An opportunity has been given to these pro- 
fessors of expressing an opinion on the work submitted to 
them, and they all agree.in considering that the subjects 
studied seem to appeal to the memory rather than to the 
faculties of observation, reflection and judgment. 
Tue Childhood Society, the object of which is the scien- 
tific study of the mental and physical conditions of children, 
has arranged a course of four public lectures to be given 
at the Sanitary Institute, commencing on Thursday, 
February 25. The lectures will be as follows :—‘ Some 
Elementary Aims in Education,’’? by Mr. Hamilton Hall; 
*“‘ Protection of Feeble-minded Children during and after 
School Age,”” by Prof. W. A. Potts; ‘‘ Physiology in the 
Curricula of Primary and Secondary Schools,’? by Dr. D. 
Sommerville; and ‘* Child Punishments,’? by Dr. H. R. 
Jones. : 
NO. 1790, VOL, 69] 
SOCIETIES AND ACADEMIES. 
LonpDon. 
Royal Society, November 26, 1903.—‘‘ On the Distribu- 
tion of Stress and Strain in the Cross-section of a Beam.’” 
By John Morrow, M.Sc. (Vict.), Lecturer in Engineering, 
University College, Bristol. 
The author describes some experiments on the measure- 
ment of lateral or transverse strains in specimens of wrought 
and cast iron when subjected to bending. The instrument 
used for the determination of the displacements of the sides 
of a beam consists essentially of two cranked levers pivoted 
together. At one extremity these are in contact with the 
points on the specimen between which the change of length 
is required, while the relative motion of the other ends is 
measured optically by means of a fixed and a tilting mirror- 
This method of measurement allows of great precision 
and delicacy of reading. In this case the lateral dis- 
placements were observed to the nearest 1/ 400000 of a centi- 
metre. 
The beams used were about 3 cm. broad and 6-5 cm. deep, 
and they were supported on knife-edges about 90 cm. apart- 
Measurements of the transverse extensions or contractions 
were made at seven different points in the depth of the beam, 
while the applied bending couple was increased by definite 
increments of about 9347 kg.cm. each. 
The actual strains proved to. be appreciably smaller than 
those which might be expected from the Bernoulli-Eulerian 
theory. 
The relations obtaining between the lateral and linear 
strains, for the materials in question, were found from 
independent experiments in direct tension and com- 
pression, and by a comparison of these with the trans- 
verse strains in the beams, the amount and distribution of 
the stresses over the cross-sections of the beams were 
inferred. 
‘The results for cast iron specimens showed that, at the 
lower loads, the longitudinal stress varies as the distance 
from the neutral axis, but that in amount it is less than 
would be expected from theoretical considerations. As the 
load is increased, however, the strain diagrams become more 
and more curved in the direction of a decreasing strain at 
greater distances from the neutral axis, and this is accom- 
panied by a displacement of the neutral surface towards the 
compression side of the beam. 
It is well known that the existing theory does not give 
a completely satisfactory account of the actions in a beam. 
This paper is therefore important, not only for its own 
results, but because it opens up a new method of experi- 
mentally approaching this and the allied subjects, and so 
facilitates further research on similar lines. 
February 4.—‘‘ Conjugation of Resting Nuclei in an 
Epithelioma of the Mouse.’’? By E. F. Bashford, M.D., 
and J. A. Murray, M.B., B.Sc. Communicated by Prof. 
J. Rose Bradford, F.R.S. 
In a previous communication the authors directed attention 
to the fact that the power of cell proliferation, which has 
been proved to occur in an epithelioma of the mouse (Jensen), 
is a phenomenon unparalleled in the mammalia. A mass of 
tumour, 16 Ib. in weight, has been produced by artificially 
transplanting portions of the original growth and its de- 
scendants. 
In seeking to throw light on this fact, the authors have 
studied carefully the phenomena which follow the transplant- 
ations of portions of the tissue to new sites, and have found 
that the tumours which arise are the genealogical de- 
scendants of the cells introduced. They have studied the 
growth of the tumours which arise at successive stages of 
twenty-four hours. In a tumour removed on the eighth 
day, and less than half a split pea in size, conjugation of 
resting nuclei has been observed. To take a specific case, 
the nuclei of two adjacent cells are continuous through the 
cell wall by a tube-like bridge, in the middle of which a 
strand of nucleolar substance with fusiform swellings in 
either cell is visible. The cells of this particular case are 
adjacent to the stroma, and close to the outer surface of 
the young tumour. 
