Geology and Mineralogy. 239 
cases light powder is sprinkled upon the water. The bell-shaped 
vessels are set with vibration in various ways.—Ann. der Physik 
und Chemie, No. 1, 1887, pp. 161-189. is ab 
Il. GEOLOGY AND MINERALOGY. 
1. Avlauea.—The map of Kilauea by Mr. F. 8. Dodge making 
Plate II, in the last number of this Journal, is reduced to one- 
fourth from the manuscript map received from Mr. Alexander, 
Director of the survey of the Islands, and the words on it, “scale 
1:6000” should be changed to 1:24,000. Plate I is reduced to 
two-thirds the original; the scale is 1:18,000. 
The writer is indebted to Prof. W. D. Alexander for a photo- 
graph (an outline copy of which is here given) of the cone within 
Halema’uma’u described by Mr. Dodge (p. 99.) It was taken 
from a point on the northeast edge of the pit on the 14th of last 
October, a few days after he finished his survey. In the copy the 
cone is in mere outline because the photograph fails to give any 
surface details. The height of the cone, as the figures in the ex- 
planation of the map, page 99, indicate, is very nearly that of the 
surrounding floor of Kilauea; and the height in the figure shows 
The cone in Halema’uma’u from a photograph taken October 14, 1886. 
that the view is one looking down into the pit, with the broken 
pahoehoe floor of Halema’uma’u (between its walls and the cone) 
in the foreground. The dotted lines indicate the positions of 
vapor-streams and clouds issuing from apertures in the sides of 
and about the cone; above it only vapors are indicated, as if 
those of the inside crater. The lower wall on the right is the 
wall of the northwest side of Halema’uma’u. 
Mr. Dodge, in a letter dated January 14th, states that the cone 
is made of broken rock, large and small fragments, derived from 
