248
THE ESSEX FIELD CLUB.
the Club. The presentation of this interesting relic was due to the kind-
ness of Mr. Ernest Linder, B.Sc., who had previously presented the Axe
used in the same ceremony. (See ante page 176.)
The thanks of the meeting were accorded to Mr. Willingale and to Mr.
Linder for this memento of an old Forest custom.
EXHIBITIONS AT THE ANNUAL CONVERSAZIONE.
Saturday, 25TH February, 1911.
Following the precedents of former years, advantage was taken of
the holding of the Annual Conversazione at the Municipal Technical
Institute to make in the Museum some exhibitions and demonstrations
of interest. The building was closed to the general public, enabling this
to be done.
Various forms of Pond-life and other objects were exhibited under
microscopes kindly lent by members of the Club. These objects were
"demonstrated" during the evening by Mr. J. Wilson, F.R.M.S. (who
furnished the bulk of the aquatic animals), Mr. John Avery and Mr.
Avery, Junr., Mr. J. C. Shenstone, F.L.S., Mr. J. Bostock, Mr. H. White-
head, B.Sc., Mr. W. Cole, A.L.S., and others.
In the small gallery, Mr. John Gray, B.Sc., A.R.S.M., Secretary to the
Anthropometric Committee of the British Association, and his Assistant
gave a demonstration of his apparatus for the Measurement of Persevera-
tion, commonly known as the "Mind Measuring Machine." When the
nerve cells of the brain are excited by an external stimulus, the excite-
ment appears to persist for a longer or shorter time after the primary
stimulus has ceased. This property of the neural matter of the brain
has a great influence on the formation of associations, and is known to
psychologists as Perseveration. In Mr. Gray's apparatus the persistence
of colour sensation is measured by the use of a revolving mirror to reflect
red and blue coloured light in rapid succession into the eye of the subject
being tested. The coloured light is produced by passing the light of
electric incandescent lamps through coloured glasses mounted on the upper
and lower sides of the apparatus. The results obtained are compared
with a table showing various mental characters associated with degrees of
perseveration ranging from Class I. "Extremely Low Perseveration"
to Class VII. "Extremely High Perseveration." The experiments proved
to be very interesting and Mr. Gray secured a large number of measure-
ments during the evening, and so attractive were they that further tests
were made on the ensuing Monday evening. (Reference should be made
to a paper read by Mr. Gray before the British Association in 1910.)
Another subject which attracted much notice was an exhibition illustra-
ting some of the points raised in the recent discussions on nourishing
forms of Bread. Samples of wheat, flour and bread were kindly sent by
many millers and bakers, and preparations and diagrams illustrating the
structure of the wheat grain and the composition of flour were shown.
Our Member, Mr. Bryan Corcoran, C.C., so well-known as an authority on
milling, gave lecturettes during the evening, and attracted attentive
audiences. Mr. Corcoran's eminently practical remarks were of the
highest value, and deserve wide diffusion. The merits of the old English