I Chemical and Photographic Section, March 8th.— 
Dr. Herapath, president, in the chair. The attendance was 
somewhat more numerous than at previous meetings of the 
section. The president read his paper, postponed from the 
February meeting, on Prof. Tyndall's researches on Negative 
Fluorescence, or Calorescence. He commenced by referring 
to the three principal divisions of refrangible rays co-exist- 
ing in thespectrumof the sun, or other intense sources of light, 
: viz.,the visible luminous ray8,the invisible chemical or actinic 
or ultra-violet rays, and the equally invisible, heating ultra- 
red rays, which were the least refrangible of all; and then 
gave a short account of the manner in which Professor 
Stokes had, by the use of certain substances, as quinine, 
uranium, &c., rendered these ultra-violet rays visible, or, in 
I other words, lowered their refrangibility, a phenomenon 
which he termed fluorescence. The problem just solved by 
Professor Tyndall was the reverse of this, viz., the increasing 
of the refrangibility of the invisible ultra-red ravs in such a 
way as to make them also visible, which was done by raising 
an incombustible body to a state of incandescence by per- 
fectly invisible raya of low refrangibility. The rays from 
the electric lamp were converged to a short focus by a small 
j concave mirror, and the whole of the light entirely cut off 
I by a solution of iodine in bisulphide of carbon. That the 
invisible calorific rays were really brought to a focus was 
readily shown by placing various combustible substances at 
jthat point, when they burst into flame, while metal leaf and 
vire was either inflamed or rendered incandescent, while, 
j strange to say, the human eye suffered no inconvenience 
jwhen placed in this dark focus, no light or heat being 
Iperceptible. 
Mr. John Beattie then made a verbal communication upon 
the Pantascopic Camera. He pointed out that since the first 
application of photography to landscapes, the great desidera- 
tum had been a lens which should have a large angular 
aperture, to take in a wide expanse of view. The first prac- 
tical solution of the problem was the fluid globular lens of 
Mr. Sutton ; several others had been proposed, but none had 
worked well. In the Pantascopic Camera the lens (Grubb's 
A. O. aplanatic) was made to rotate on a dead perpendicular 
centre from right to left, while the plate was moved in a 
rectilinear direction from left to right, the movements being 
regulated by clockwork. By this contrivance an angle of 
120° could be taken with ease, and even the whole horizon 
of 360° if desired. Bv means of a peculiar tliaphragm, very 
perfect atmospheric effects of cloud, &c., were obtained, and 
the action was so rapid, only one-fifth of the usual time of 
exposure being required, that moving figures in a Inndscape 
were perfectly reproduced. Mr. Beattie illustrated his 
remarks by some very beautiful panoramic photographs 
taken by this method, and concluded by describing Swan's 
carbon-printing process, specimens of which were also 
shown. 
Entomological Section, March 14th. — Mr. Stephen 
Barton, president, in the chair. Mr. Harding exhibited the 
following species of Lepidoptera:— Lophopteryx Carmelita, 
the larva of which feeds upon birch, formerly a great rarity, 
and only taken occasionally now. Gastropacba Ilicifolia, 
male and female; the larva feeds upon Vaccinum myrtillus; 
this insect has occurred in England only near Rugby and 
Sheffield, but is common on the continent. Hyria auroraria, 
said to have occurred at one time in the Bristol district; the 
larva feeels on plantain. Ephyra orbicularia, captured at 
Brighton ; Acidfiiia emutaria, at Lyndhurst ; and A. 
degeneraria, at Portland, by Mr. Harding. A. rusticata. 
A. ochrata occurs only at Southend, in Essex. The 
larva; of the last four species are at present unknown. 
Alencis pictaria, captured at Dartford - heath. Fidonia 
carbonaria occurs in Perthshire. The Secretary exhibited 
fourteen species of the genus Meligethes, and also a series 
of Carpophilus hemipterus. 
