204 
POrULAR SCIENCE RETIEIV. 
Crystals of Glycerin. — These somewhat peculiar bodies are described by 
Herr von Lauge, in “ Pogg. Annal.” The “ Chemical News” of Feb. 12 
says, “ that the examination of these crystals was attended with difficulty, 
as when taken out of the mother-liquor they melt away, and render the 
application of the reflecting goniometer impossible. They belong to the 
rhombic system; their elements are a : b : c = 1 : 070 : 0'66; the forms are 
100, Oil, 101, 111. Cleavage imperfectly perpendicular to the longitudinal 
axis, therefore parallel to a plane 010. 
GEOLOGY AND PALAEONTOLOGY". 
The Drift in Kansas , TJ.S.A. — The Rev. M. Y. B. Knox has written a 
letter to Mr. Dana, which is published in “ Silliman’s American Journal ” 
(Dec. 1874). He says that “the drift in Kansas is confined mostly to the 
northern half of the State, little having been found any distance south of the 
great Kansas Yallev. North of this river, especially in the region north and 
west of Topeka, there are drift rocks of vast size. The prevalent kind of 
rock is red and flesh-coloured quartzite, with a mixture of conglomerate and 
trap ; the mass is red quartzite. On the high prairie these boulders are 
sometimes from six to fifteen feet in diameter ; yet in the north-east fourth 
of the State one may ride twenty miles over the prairies and not see one of 
so large size. Smaller boulders and pebbles are everywhere to be found in 
this part of the State.” 
The Hawaiian Volcanoes. — According to the recent statement of Mr. T. 
Coan, Kilauea has been very active for the greater part of the past year. The 
great South lake has been full and overflowing much of the time ; and the great 
central depression of 1868 in the crater has been filled up by deposits about 
200 feet, while the region around the great South lake (Halemaumau) is a 
truncated mountain, nearly as high as the outer upper edge of the crater 
Mokuaweoweo ; the summit crater of Maun a Loa has been in action for 
eighteen months. For the most of the time the action has been violent. Of 
late it has decreased, and there is the appearance that it will soon cease. 
He also says they have had few earthquakes at Hilo during the year, and 
these have been feeble. They are often felt near Kilauea, in the district of 
Kau. 
Tortoises of Mauritius closely related to those of the Galapagos , places that 
are nearly antipodes to one another. — Dr. A. Gunther, in a memoir on “ The 
Living and Extinct Races of Gigantic Land-Tortoises,” Parts I. and II. of 
which have been published, states that there are remains of gigantic 
tortoises on Mauritius and the neighbouring island of Rodriguez associated 
with those of the Dodo and Solitaire, which indicate that the races have 
only recently become extinct. They differ from other tortoises of the 
region in having a flat cranium and truncated beak, and in this respect they 
have the greatest affinity with the tortoises still inhabiting the Galapagos 
Archipelago. Dr. Gunther observes that the presence of these allied 
tortoises at points so remote from one another can be accounted for only on 
the view that they are in each case indigenous. 
