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RELATIONSHIP BETWEEN THE BONE-CELLS AND THE 
GLOBULES OE THE BLOOD. 
The cells of bone differ in size in almost every animal; so 
that the microscopist is enabled, by the examination of a 
section of a bone, from its structure to determine whether it 
belonged to a man, an animal, a bird, or a fish. 
“We are indebted,” says Dr. Lankester, " to Professor 
Quekett, of the College of Surgeons, for having pointed out a 
remarkable fact with regard to the bone-cells, and that is 
that they correspond in size with the size of the blood- 
globules. Animals contain a quantity of cells called blood- 
cells, which vary in size in different animals. In the human 
being the globules are the 3500th part of an inch in diameter, 
and the bone-cells are the 2000th of an inch. In birds the 
bone-cells are about the 5000th of an inch in diameter, 
whilst the blood-globules are the 6000th. In reptiles the 
globules are not more than the 700,000th of an inch in 
diameter, and the bone-cells not more than the 500,000th. 
There is then a general correspondence between these two 
bodies, but there are numerous exceptions, and the law does 
not hold in all cases.” 
GENERAL DIFFUSION OF ARSENIC. 
Du. Griffin, in a letter to the editor of the “ Chemical 
News” says — c( We live surrounded by means of uncon¬ 
sciously absorbing traces of arsenic. We breathe arsenicated 
dust from the green flock papers on our walls; arsenical 
papier moure lies soaking on dishes afterwards used for culi¬ 
nary purposes ; arsenic is contained in glazed green papers 
which are often employed for wrapping cocoa and other 
articles of food, and confectioners supply it wholesale in their 
cake ornaments. The very drugs prescribed for our relief, 
especially the compounds of bismuth, are tainted with arsenic, 
and it has even been detected in carbonate of soda. Nay, 
more, even our vegetable food, as Professor Davy has lately 
pointed out, may be contaminated with arsenic derived from 
superphosphate manure, and there is probably no drinking 
water containing iron without a trace of arsenic as well. 
Now, metals are remarkably prone to become localised in 
particular organs; the “dropped joints” of painters are 
