ee 
192 General Notes. [March, 
Guinea, forming materials for a history of the discovery of this 
country by Spanish navigators from 1528 to 1606, with a map. 
M. Marche has returned from the west coast of Africa after 
exploring Upper Ogooné. M. Wiener has finished his explora- 
ions of the Andes. Mr. N. B. Wyse, member of the Interna- 
tional Society of the Interoceanic Canal by the Isthmus of Darien, 
is now making a new exploration in this region. 
Prof. Mohn, in Petermann’s Mittheilungen for January, gives an 
original map of the relief of the sea-bed between the British 
Isles, Norway, Spitzbergen and Greenland. On this the contour 
lines of equal depths for each 100 fathoms are shown, and the grand 
feature of this region, the submarine barrier which passes from the 
north of the British Isles across by the Fare islands and Iceland 
to Greenland, rises for the first time distinctly to view. | It is this 
great barrier, says the Academy, that mainly determines the con- 
ditions of the deep seas on each side of it. The depth of the 
Atlantic on the south-western side are filled up with warmer 
water, but as soon as the barrier is crossed this is limited to the 
uppermost strata. On the Atlantic*side of the ridge a mass of 
e 
Atlantic. Prof. Mohn also proposes that the sea between Norway 
and the Farée islands, from Mayen and Spitzbergen, which has _ 
never been distinguished by any special name, be called the “Nor- 
wegian sea.” 
Gerhard Rohlfs is to undertake a new journey of exploration in 
the Eastern Sahara, which is planed to extend over five years. 
MICROSCOPY .! 
Buttocn’s Microscopes. — Mr. W. H. Bulloch, 126 Clark 
street, Chicago, has issued a well illustrated description of his re- 
cent improvements in the construction of the microscope, in 
which appear several points of novelty and importance. The new 
large stand is literally full of ingenious contrivances, and without 
being clumsy or unduly complicated seems to combine more 
really useful adjustments than any other stand containing the 
modern improvements, 
The sub-stage and mirror bar both swing around an axis in the — 
plane of the object on the stage. Mr. Bulloch claims, with much 
reason, to have been the first to apply such an adjustment to 
the sub-stage, and he now mounts the mirror bar in a similar 
manner, the two being made to move either together or sepa- 
rately, and either by hand or with a mechanical motion; 
or the sub-stage with its milled heads can be entirely removed. 
_ Thus is attained a facility not hitherto equaled of using either 
_Sub-stage or mirror or both together at any angle below the stage 
_ This department is edited by Dr. R. H. Ward, Troy, N. Y. 
