804 KANSAS CITY REVIEW OF SCIENCE. 
stratifications, the same in the Tyrol and in the Canaries—proofs of the subter- 
ranean activity of the earth. Cordier, also concluded from the increasing tem- 
perature of mines with their depths that the mass of the globe was still ina fluid 
state. M. Elie de Baumont has based his vast system on this crust of the globe 
contracting by cooling. He astonished scientists also by asserting that the oldest 
mountains, were not the highest, and that little hills in Britany and Wales, were 
older than the Alps and the Andes. ‘The classification zodlogic and the clas- 
sification by systems of dislocations and upheavings, to-day march side by side. 
Professor Daubrée points out that by no means can feldspar or analogous silicate 
tocks be formed independent of heat, that the fissures in the rocks filled with 
metals, have been in intimate relationship with the internal regions of the globe 
M. Perroncioto has made some further researches as to the cause of the 
anemia which affects the workmen in the St. Gothard tunnel. He found the 
patients were invariably suffering from quantities of worms, like small eels, 
whose presence sufficiently explained the malady. The same diagnosis was ob- 
‘served in the case of the men who bored the Frejus tunnel. 
Teeth have a very intimate connection with health; bad teeth imply a bad 
stomach, and a stomach which functions badly contributes to caries and the loss 
of the teeth. From the very earliest history, the preservation of the teeth occu- 
- pied attention. Homer, Hesiod, Euripides, etc., constantly allude to the sub- 
ject. In the law of the Twelve Tables, it was prohibited to bury the dead with 
gold, except when that metal served to bind the teeth. Cascellius, the famous 
dentist at Rome, left, when dying, a fortune greater than that of a pro-consul. 
‘Tooth preservatives or powders, were also in great request in ancient Greece. 
Young ladies ever had a portion of myrtle, the shrub sacred to Venus, in their 
mouths, and St. Clement blamed the ladies of his day for their coming to the 
temple with their mouths full of the drug mastic. The adult has sixteen teeth in 
each jaw, the child but ten, till seven years of age. A tooth consists of the crown 
which extends outside the gum, the neck, which is covered by the gum, and the 
root, which occupies the socket. The tooth is hollow, and filled with a pulp; 
‘closed toward the crown, but open at the roots to allow the nerves and blood 
vessels to ramify. Three different tissues compose the teeth: the ivory or dent- 
ine, which exists at the root, as well as at the crown, and forms the principal 
part, it is not bone, as many think, though it has the same chemical composition, 
no vessel penetrates it, and it has neither medullar sap, nor pores, it consists of 
of layers, one over the other, and hardened even at the moment of formation. 
Next, the enamel, which covers the crown of the tooth, and that resembles not 
a little porcelain, the shade varying with the temperament of each individual. 
It is so hard as to resemble blue steel, it marks the best files, and will strike fire 
with steel, like a flint; third, the cement, which covers the tooth, and thicker at 
the root than at the neck. The teeth live and grow by means of their pulp, a 
matter extremely sensitive, and when inflamed, very painful, in consequence of 
the impossibility to augment its volume, being narrowed in on all sides by the 
