THE PUNCHBOWL 43 



versally inward from the exterior rim and similarly outwardly from the 

 edge of the crater. The best place to examine the beds is at a quarry 

 at the southwest base below the reservoir. A space as much as 500 by 

 400 feet has been excavated to the depth of 40 or 50 feet. Many irreg- 

 ularities in the dip are exhibited, particularly two upward bulgings 

 with small faults. Photographs show this imperfecta . Nearly vertical 

 seams are lined with a calcareous incrustation, originating presumably 

 in connection with the outburst through limestone. A few spherules of 

 thomsonite occur and fragments of vesicular basalt. An artesian well 

 at the Queen's hospital has penetrated through this tuff, showing an ex- 

 tension of the volcanic mud in that direction. The underlying material 

 of the plain seems to be shown in a pit on Vineyard street, where there 

 was exposed 15 feet thickness of earth with rolled pebbles and marine 

 shells. At a quany 1,000 feet east from the one named, there are layers 

 of a black, compact rock, perhaps a finer mud consolidated. Interest- 

 ing sections showing the relations of the cindery ashes to the tuff will be 

 described later. 



At the upper side of the reservoir is an interesting dike cutting the tuff 

 vertically and underlying the ashes. It is a basalt slightly chrysolitic, 

 3 feet wide, running in the direction of the summit, and with two others 

 mentioned by Brigham near the ravine, one 2 and the other 10 feet 

 wide, now covered by debris, have cut the tuff radially. The reservoir 

 dike shows differences between the outer and inner portions, that on the 

 outside being finer grained and the inside a breccia. Both are vesicular. 

 There are joints parallel to the walls, some of them coated with lime. 

 About 10 feet of the dike are clearly exposed here. Seventeen hundred 

 feet lower down in the direction of the dike, at the pumping station, there 

 has been a recent volcanic ejection of red clinker, a sort of blow-hole, 

 not unlikely connected with the filling of the chasm. At the summit of 

 the road, where it winds around a flag-staff close to the battery, there are 

 fine exposures of the black cinder ash, with included nodules, red clinker, 

 and compact basalt, slightly porphyritic, by black crystals of pyroxene. 

 The whole interior of the basin is covered by loose black ashes, weathered 

 to brownish red at the surface. In Dixon's " Voyage around the World " 

 there is a picture representing the Punchbowl in 1786. In the sketch the 

 eastern part of the rim is the highest, much as it appears from Rocky hill 

 at the present time. Plate 7 represents Punchbowl as it is seen from the 

 east from a higher elevation. The drainage outlet is at the extreme left. 



DIAMOND HEAD OR LEA HI 



This is the most perfect, as well as the best known, of all the secondary 

 craters about Honolulu. Visitors recall it as the prominence seen just 



