H. C. Sargent—Axinite Veins, Penmaenmawr. 5 
result from the flexing of the whole crust, resulting from the tidal 
action of the moon and from undue stresses arising from denudation. 
In the construction of the Panama Canal movement of the beds took 
place to a large extent. 
But would “the settlement of a high gravity material into one of 
lower gravity produce results resembling Trail and Underplight ? 
That such would be the case I have attempted to demonstrate in the 
following manner :—Into a shallow cardboard box a layer of pitch 
about 1 inch thick was poured. Upon this, when cold, a layer of 
sealing-wax mixed with fine and coarse sand was run. When the 
whole was quite cold the cardboard box was slung beneath an 
inverted incandescent gas burner. In this way the wax and pitch 
were slowly heated from above downwards and the viscosity reduced. 
Under these conditions the weighted wax slowly sank in irregular 
patches into the black pitch, which rose up around the descending 
wax. After the lapse of ten hours the cardboard box was removed 
and its contents allowed to cool, and when quite cool the cake of 
Fic. 2.—W, Wax; P, Pitch. 
wax and pitch was broken through, Fig. 2 showing a trace along one 
of the lines of fracture. It will be seen that the forms assumed by 
the heavy wax closely resemble Trail, whilst the pitch assumes the 
form of Underplight. Close examination shows that the coarse 
grains of sand, especially near the sides of the descending masses of 
sealing-wax, stand i in a vertical position as do the stones in Trail. 
The above experiment does not, of course, prove that Trail and 
‘Underplight were actually formed in the manner assumed; but it 
does show that.a bed of sand or gravel spread over a bed of soft clay, 
if rendered slightly fluid at times by repeated thawing, would most 
probably settle into a form which would resemble Trail and 
Underplight. 
One of the points of interest is that deep freezing and thawing of 
the soil is required to produce the effect. We are dealing, therefore, 
not merely with conditions which are interesting as being a probable 
explanation of the method of the formation of Trail and Underplight, 
but with features which (in areas where soft clays occur and signs 
of true glaciations are absent) should enable us to ascertain when 
cold periods have occurred. 
JIT.— Axinire Veins In tHE PenMarnmawr PorpHygite. 
By H. C. SARGENT, F.G.S. 
N the course of a visit to North Wales last summer my friend 
Mr. Ivor E. Davies, of Penmaenmawr, called my attention to 
a mauve mineral, forming thin veins, in the intrusive porphyrite of 
