4.5
-34.2
  7.4
 12.6
 -2.5
  1.7
-34.0
  7.3
 15.4
 -3.8
  2.9
 -4.2

The values are the 12 differences that come from 12 matched pairs of observations.
The data are given and described on pp. 38-39 of Miller's Beyond ANOVA: Basics of
Applied Statistics.

12 donors gave two bags of blood.  All 24 bags contained ACD, and one of the bags 
from each donor had adenine added.  After a period of time the amount of antihe-
mophilic globulin (AHG) was measured, for each bag, and differences of the form 
ACD+A - ACD were computed for the 12 pairs of bags.

One can do statistical tests to determine if there is strong evidence that the
addition of adenine effects the amount of AHG.