SCIENTIFIC SUMMAKY. 
315 
other, may give rise to woody deposits of considerable thickness. If in the 
spring one introduces a plate of gold or platinum between the bark and the 
sap (? cambium), one finds in the autumn that a complete woody layer is 
formed external to the plate, and quite apart from the cambium. But the 
plate has not changed its position, and its inner face is exactly in the 
position where the old wood lay at the commencement of the experiment. 
From this the author concludes that the new woody formation was in no 
way due to any anterior formation. — See Comjotes Hendiis, March 30. 
Developjnent of Bacteria . — M. Bechamp, in a note, which was read to tho 
Academic des Sciences on May 4, entered into a long account of the 
developmental relations of Bacteria and Mycrozymee. Indeed he considered 
the latter to be the first stage of the former. The Mycrozymee are nor- 
mally simply minute spherical bodies. In this state they exist normally in 
the human body. But when the tissues are exposed to the air they grow 
into chains and become Bacteria. MM. Bechamp and Estor seem to think 
it a proof of these Baeterias being normal constituents of the body, that they 
are found in the liver. But after all, what is to prevent any organic germs 
from reaching the inmost centre of the liver, through the mouth, stomach, 
and gall duct ? 
CHEMISTKY. 
A new Aspirator, which may be found useful by some of our chemical 
readers, has been described by J. Landaner, in the Chemical Neivs (March 
20). The new instrument is based on the principle of the syphon. A capacious 
flask is hermetically closed by a cork provided with two holes. One of the 
latter receives the syphon, and the other a glass tube for connecting the 
apparatus, through which the passing of a current of air is desired. After 
having made the connections and filled the flask with water, the latter is 
made to run out of the flask by sucking the outer leg of the syphon, the 
end of which must, of course, be lower than the level of the water. The 
current of air is thus effected. The efflux of water is regulated by joining 
more or less width to the tubes between apparatus and aspirator. Two as- 
pirators are connected with the apparatus, and used alternately, in order to 
enable a refilling of the flasks without interruption of the process. For 
this purpose an intermediate apparatus, consisting of a glass tube about two 
inches long, and one inch wide, is required, which is connected on one side 
with the apparatus intended for receiving the current of air, and on the 
other side with the two aspirators. The latter connection may be effected 
by india-rubber tubes, each provided with Mohr’s pinch-cock. Such ar- 
rangement will enable the alternate working of the two aspirators. It is of 
course understood that all the connections must be effected hermetically. 
One of the advantages of this aspirator is, that it allows an easy determi- 
nation of the quantity of air passed through by employing graduated 
vessels. 
Absorption of Arsenic, Tungstic, and Arsenious Acid by Charcoal . — Mr, 
Skey writes to the Chemical Neivs to say that charcoal absorbs all these sub- 
