434 
POPULAK SCIENCE KEVIEW. 
on the surface of the liquid, and which had all the appearance of leucin. 
Repeated recrystallisation from boiling alcohol gave it pure, in the form of 
small spheres of sharp outline and radial in structure. Its reactions proved 
it to be leucin. The author believes, with DragendorfF, that the substance 
obtained by Reinsch from the juice of Chenopodium album , and called cheno- 
podin, is really leucin. 
Spontaneous Generation from a Chemical Point of Vieiu. — Professor Debus, 
F.R S., in delivering an address before the British Association at Belfast, 
said that one of the most perplexing problems in physiological inquiry was 
the question — What is the origin of the lower forms of life which are 
supposed by some to be formed spontaneously from inorganic material ? 
He proposed to consider the question entirely from the chemist’s point of 
view. The question was — Was it possible that the lower forms of life 
could be produced as the mere spontaneous work of inorganic material ? 
Some philosophers believed that such a formation was possible. Darwin, in 
his work, propounded a certain view about changes which animals under- 
went when the external conditions under which they lived became changed. 
By experiments, and drawing conclusions from them, he did not go so far as 
to assert it was possible that from inorganic matter organic life could be 
originated. He never said that, though some followers had expounded his 
theory as going to that length. He (Professor Debus) thought that this 
question was really one in chemical science. By inorganic matter he 
meant matter that met their senses — as a piece of flint — and by organic 
matter was to be understood the substances which were found in the 
bodies of animals and plants. Professor Debus proceeded at some length 
to consider the question chemically, and concluded by saying that the 
Jesuit of the experiments of chemists was that there were not any con- 
ditions favourable to the formation of organic matter from inorganic 
material ; that, on the contrary, life was destroyed when the temperature 
was raised beyond a certain point; and chemistry also showed that in 
former ages there did not exist the conditions which would enable organic 
life to be formed from inorganic matter. 
Blue Pigment of the Egyptians. — Fifteen centuries before the Christian 
era the Egyptians appear to have been acquainted with the preparation of 
three distinct kinds of blue pigment, prepared from mixtures of sand, 
soda, and lime, with oxide of copper. One of these fine colours has been 
lately examined by M. Henri de Fontenay, who contributes a paper on the 
subject to the .Tune number of the “ Annales de Chimie.” The investigation 
was conducted in Peligot’s laboratory, at the Conservatoire des Arts et 
Metiers, and some examples of the blue frit were then made at the 
National Porcelain Factory at Sevres, under M. Salvetat. The author 
publishes not only analyses of ancient specimens, but recipes for their 
imitation. A mixture of 70 parts of white sand, 25 of chalk, 15 of oxide 
of copper, and 6 of dry carbonate of soda, yielded, when fritted together, a 
blue material said to be equal in colour, texture, and durability to the 
ancient examples. 
Chemical Constitution was the subject of an address before the British 
Association (Belfast), by Dr. Crum Brown. He first pointed out that the 
phlogistic controversy, which resulted from the discovery of oxygen, termi- 
