A method of shaft sinking through loose waterlogged sands that are not suitable for the cementation sinking method. Rings of lined boreholes are put down outside the proposed shaft and in them a very cold solution, such as brine, is circulated until an ice wall has been formed sufficiently thick to enable sinking to proceed normally. The method consists of the following stages: (1) forming a protective wall of ice, with its base in an impervious deposit; (2) maintaining the ice wall until the sinking and lining of the shaft has been completed, and (3) thawing out the ground without damage to the shaft. The freezing method has been revived, largely due to the successful use of bulk concrete, backed by corrugated sheets in place of tubbing, for lining the shaft through the frozen ground. This is followed by wall grouting. Freezing was introduced originally in 1883 by F. H. Poetsch.