440 SCOTT'S LAST EXPEDITION 



Under summer conditions, such as were contemplated, \\ hen there was 

 less cold for the men to endure, and less firing needed to melt the snow for 

 cooking, the fullest allowance of oil was I gallon to last a unit of four 

 men ten days, or V4o of a gallon a day for each man. 



The amount allotted to each unit for the return journey from the 

 South was apparently rather less, being % gallon for eight days, or %8 gal- 

 lon a day for each man. But the eight days were to cover the march from 

 depot to depot, averaging on the Barrier some 70-80 miles, which in nor- 

 mal conditions should not take more than six days. Thus there was a sub- 

 stantial margin for delay by bad weather, while if all went well the surplus 

 afforded the fullest marching allowance. 



The same proportion for a unit of five men works out at % of a gallon 

 for the eight-day stage. 



Accordingly, for the return of the two supporting parties and the 

 Southern Party, two tins of a gallon each were left at each depot, each 

 unit of four men being entitled to % of a gallon, and the units of three and 

 five men in proportion. 



The return journey on the Summit had been made at good speed, taking 

 twenty-one days as against twenty-seven going out, the last part of it, from 

 Three Degree to Upper Glacier Depot, taking nearly eight marches as 

 against ten, showing the first slight slackening as P.O. Evans and Oates 

 began to feel the cold ; from Upper Glacier to Lower Glacier Depot ten 

 marches as against eleven, a stage broken by the Mid Glacier Depot of 

 three and a half day's provisions at the sixth march. Here, there was 

 little gain, partly owing to the conditions, but more to Evans' gradual 

 collapse. 



The worst time came on the Barrier ; from Lower Glacier to Southern 

 Barrier Depot (51 miles), 6^ marches as against 5 (two of which were 

 short marches, so that the 5 might count as an easy 4 in point of distance) ; 

 from Southern Barrier to Mid Barrier Depot (82 miles), 65^ marches as 

 against 53^; from Mid Barrier to Mt. Hooper (70 miles), 8 as against 

 4^4) while the last remaining 8 marches represent but 4 on the outward 

 journey. (See table on next page.) 



At to the cause of the shortage, the tins of oil at the depot had been 

 exposed to extreme conditions of heat and cold. The oil was specially vola- 

 tile, and in the warmth of the sun (for the tins were regularly set in an 

 accessible place on the top of the cairns) tended to become vapour and 

 escape through the stoppers even without damage to the tins. This process 

 was much accelerated by reason that the leather washers about the stoppers 

 had perished in the great cold. Dr. Atkinson gives two striking examples 

 of this. 



1. Eight one-gallon tins in a wooden case, intended for a depot at Cape 

 Crozier, had been put out in September 191 1. They were snowed up; and 

 when examined in December igi2 showed three tins full, three empty, one 

 a third full, and one two-thirds full. 



2. When the search party reached One Ton Camp in November igi2 

 they found that some of the food, stacked in a canvas ' tank ' at the foot 



