One of the most popular and commonly used methods of preserving eggs is by means of water glass. Though this method was introduced only comparatively recently it has largely superseded older methods, and also appears to have led to much more frequent preservation of eggs on the small scale in households and by small traders. The method is simple and effective. The eggs are obtained when they are plentiful and cheap in spring and preserved for use during the winter months. It is therefore necessary to keep them for about six months. In the experiments described below some were left in a solution of water glass as long as four years.