FACTS AND OBSEllVATIONS. 
917 
new mode of heating upon the metal itself, one of the dock¬ 
yard operatives declared, somewhat emphatically, that the 
commonest iron treated by it came out of the furnace as 
good as the best Low Moor. The apparatus is simple, and 
inexpressibly applicable to existing coal-furnaces. It con¬ 
sists of a reservoir, from which the oil is pumped up as 
wanted into a receiver, where, by the application of heat, the 
vapour is generated, and this is passed through pipes into 
the furnace, and used as fuel in the ordinary way.— Pojoular 
Science Review. 
The Vascular parts of the Retina of the Hedge¬ 
hog. —The Proceedings of the Royal Society, May, contains a 
communication by Mr. J. W. Hulke, in continuation of his 
former papers on the structure of the retina. The chief 
peculiarity, he says, is that only capillaries enter the retina. 
The vasa centralia pierce the optic nerve in the sclerotic 
canal, and, passing forwards through the lamina cribrosa, 
divide at the bottom of a relatively large and deep pit in the 
centre of the intraocular disc of the nerve, into a variable 
number of primary branches, from three to six. These 
primary divisions quickly subdivide, furnishing many large 
arteries and veins, which, radiating on all sides from the 
nerve-entrance towards the ora retina, appear to the ob¬ 
server's unaided eye as strongly projecting ridges upon the 
inner surface of the retina. When vertical sections parallel 
to and across the direction of these ridges are examined 
with a quarter-inch objective, it is immediately perceived 
that the arteries and veins lie, throughout their entire course, 
upon the inner surface of the membrana limitans interna 
retinaea betw'een this and the membrana hyaloidea of the 
vitreous humour, and that only capillaries penetrate the retina 
itself.— Ibid. 
Oats as Protein-yielding Plants. —Herr Dr. Kreusler 
has a paper on this subject in the Journal fur prahtische 
Chemie (No. 9). He found that the protein compound was 
extracted from the coarse oatmeal by means of alcohol of 
ordinary strength—80 per cent. He states the composition 
of the pure substance to be in 100 parts—C. 52'59, H. 7*65, 
N. 17*71, S. 1-66, O. Q0-S9.--Ibid. 
The Nutrition of Plants. —In a paper lately laid 
before the Society of Sciences of Gottingen, Herr W. Wicke 
communicated some results of researches upon the nutrition 
of plants. H^ had been experimenting on plants with phos¬ 
phate of ammonia, hippuric acid, and creatine. He con- 
