In case the text is hard to read, the bar chart above shows percentage area of gaps for four different brains. #1 (left) was treated by stepped concentration of glycerol-10%, 20%, 40%, 75%. #2 was the same, except it also contained 5% DMSO. #3 was handled the same as #2, except that the results were different because of individual variation-this brain did not show as much shrinkage to the naked eye, presumably because of impaired circulation. #4 was a control, not perfused but frozen in the same way.

In each case, the left or blue bar represents a sample from the outer layer, the middle or red bar the middle layer, and the right or yellow bar the outer layer.