Cambridge Underground 1982 p 9-10

115 provisional survey (1981)

A4 survey at 100 dpi - 20 k gif


The Survey

Surveying was not the strong point of this year's expedition; it is hoped that we can do better next year. The entrance series of 115 to the head of the Ramp and 41 down to the pitch just above Junction Chamber were surveyed to BCRA grade 5 in 1980 and these surveys have been published in Proc. UBSS Vol. 16(1). 115 from the ramp to the bottom of the pitches and the connection were both surveyed to Grade 4 (the survey of the connection is reproduced here), making a closed traverse with the surface survey between the entrances. Unfortunately, though they closed vertically to within 2m, the plan closure was wildly out. It is thought that this might have been due to a sticky compass on the 1980 survey. The length of Pete's Purgatory was found to be 800m, but no other details were measured. Below this, the section of the streamway from the inlet to the 'twelve foot climb' (marked as c5) was surveyed to grade 3 and this is extrapolated downstream on the grade 1 survey to give a total depth of 680m plus or minus 40m. One point which the elevation does not bring out is the way that Stellerweg spirals round on itself with changes of direction at the big pitch and at Junction Chamber. The final direction of the streamway seems to be northwest - heading back into the mountain and away from the lake.