58 
REPORTS OF SOCIETIES. 
in the former, and a much greater amount of slag is formed, which 
increases the loss of iron and diminishes the useful effect by one 
fourth to one third. In both methods the refining is carried on till the 
iron is malleable, and the necessary amount of carbon added in the 
form of Spiegel-eisen or ferro-manganese. An essential feature in the 
Basic process is the successive stoppages for test samples, which pro¬ 
long the operation. There is also uncertainty of sufficient dephospori- 
sation. One point more of very great importance remains to be noted. 
The phosphorus is very little affected as long as any carbon is present, 
so that an “after-blow” is necessary to remove the phosphorus. Now, 
on adding the ferro-manganese some of the phosphide of iron in the 
slag is reduced by the carbon monoxide liberated, so that the amount 
of phosphorus in the final product is greater than in the malleable 
metal at the end of the ordinary blow. Therefore the great desidera¬ 
tum of the Basic process is avoidance of the after-blow, which at 
present is essential. 
BIRMINGHAM MICROSCOPISTS’ AND NATURALISTS’ 
UNION.—This Society has removed its place of meeting to more 
commodious and central premises, 20, Paradise Street, next door 
but one to the Midland Institute. On the opening night, January 
21st, a “ Special Microscopic Exhibition” took place, when a good 
show of instruments was made. The exhibits were chiefly living 
organisms, and proved very interesting to those present. Meetings 
are held evei’y Monday evening at 7.30, when the attendance of all 
interested in natural science is earnestly invited. As the Society was 
formed solely to promote a love for natural objects all students and 
lovers of Nature who may visit its rooms will be sure to meet with a 
cordial welcome. 
CHELTENHAM NATURAL SCIENCE SOCIETY.—Decem¬ 
ber 20th.—Mr. H. Matthews delivered a lecture on “ The Optical 
Characters of Crystals.” which was beautifully illustrated by experi¬ 
ments. Beginning with a general idea of wave motion as derived from 
the observation of the disturbance created in a still pond by throwing 
in pebbles, he passed on to the motion of the luminiferous ether, and 
then to double refraction. The action of a pair of Nicol’s prisms 
was then illustrated, and the effect of introducing between them a 
plate of selenite. A curious effect was produced by splitting the 
selenite thinner and thinner, while still holding it between the prisms ; 
as the thickness of the slices was very variable, a gorgeous display of 
colour was obtained. After explaining the theory of the production of 
these colours, the lecturer placed a thin film of liquified benzoic acid 
between the prisms ; no colour was produced, but as it cooled crystal 
after crystal was formed, and their images flashed on the screen in 
brilliant hues. Mr. E. Wethered exhibited the sporangia of carboniferous 
plants from the lower limestone shales of the Forest of Dean, which 
were similar to those found in the black shales of Ohio, from which 
oil is derived. 
NOTTINGHAM NATURALISTS’ SOCIETY.—January 15th.— 
Mr. J. S. Hedderley read an instructive paper by Capt. Becher, R.A., 
of Southwell, entitled “ About Birds.” At the conclusion of the paper 
an interesting discussion followed, in which Messrs. Wheatley, Blandy, 
Musson, and Hedderley took part. The Annual Meeting of the 
Society was held on Tuesday, January 8th. The President, Dr. E. 
