In these days when there are few Breweries which do not possess a Microscope, it would seem desirable that the instrument should not fall a prey to the casual or uninstructed observer, but should rather, by the knowledge and skill of those that use it, be made a means of controlling the processes of Malting and Brewing. A Brewer in becoming practically acquainted with the Microscope as a controlling agent in his process, raises, to use a figure of speech, a part of the line of fortification which science provides against the hurtful or injurious influences declaring themselves, when Brewing operations are not conducted with the intelligence and skill that they ever increasingly require.