EVIDENCE AS TO CLIMATIC CONDITIONS. 149 
oxidizing by unfavorable conditions, of which cold was one. By contrast 
it may be inferred that the temperature was higher—that is to say, the 
climate was milder—when the Orting gravels were stained with oxide 
of iron. 
Decomposition of iron minerals.is promoted by decaying vegetation, 
and in many formations of various ages the occurrence of iron deposits 
is associated with peat or lignite. The presence of iron oxide in the 
Orting eravels thus suggests the development of vegetation in the region 
after the retreat of the Admiralty ice-sheet. 
Lignite occurs so generally in formations belonging to the Puyallup 
epoch that the evidence of iron oxide in the gravels is of minor conse- 
quence. Its distribution in bluffs along Admiralty inlet has been ob- 
served by Russell; but before quoting his observations I wish to note 
an occurrence in Carbon River canyon, which can be definitely correlated 
with the Orting gravels. On the north side of the river, 1.25 miles below 
Carbonado, a short railroad cut exposes a section through a remnant of 
sandy clay which rests on Kocene strata. The remnant is preserved 
from erosion by a boulder, 8 feet in diameter, which is partly buried in 
gravel on top of the clays. The clays contain lignite. It occurs in bits 
arranged with the horizontal stratification and in larger pieces, one of 
which was a slab of wood 4 feet (1 meter) in length. The elevation of 
the lignite bed is 570 feet (174 meters) above sea, in the horizon of the 
Orting gravels. 
At first sight this occurrence might be aie sbeted to the modern river 
in whose channel lie the clay and boulder, but it is obvious that the 
torrent which could possibly roll the great stone would simultaneously 
wash away the clay and lignite. The even bedding of the deposit was 
the work of comparatively quiet water, and the boulder was dropped by 
ice into its present seat. The relations thus demonstrate the simul- 
taneous presence of driftwood and ice. The suggestion that the lignite 
is of earlier origin, and was deposited as lignite rather than as wood, is 
apparently negatived by the character of the lignite. It is unlike the 
Hocene lignites and like those of the interglacial epoch. 
The remnant of lignite bearing clays lies between the railroad and the 
river. On the farther side of the track is a bluff of Hocene shale. Thus 
the clays lie close to the foot of a cliff, which had developed before the 
Orting gravels were deposited, which was buried by the gravel and by 
subsequent formations, and which has been resurrected by the present 
river. ‘The occurrence is therefore of importance in its bearing on the 
character of the topography during the Pleistocene period. 
In a report from the field after making a reconnaissance of Admiralty 
