beers. Many breweries were still brewing oatmeal stouts in the 1950s, for example Brickwoods in Portsmouth, Matthew Brown in Blackburn and Ushers in Trowbridge. When Michael Jackson mentioned the defunct Eldrige Pope "Oat Malt Stout" in his 1977 book The World Guide to Beer, oatmeal stout was no longer being made anywhere, but Charles Finkel, founder of Merchant du Vin, was curious enough to commission Samuel Smith to produce a version. Samuel Smith's Oatmeal Stout then became the template for other breweries' versions. Oatmeal stouts do not usually taste specifically of oats. The smoothness of oatmeal stouts comes from the high content of proteins, lipids (includes fats and waxes), and gums imparted by the use of oats. The gums increase the viscosity and body adding to the sense of smoothness. Oyster stout Oysters have had a long association with stout. When stouts were emerging in the 18th century, oysters were a commonplace food often served in public houses and taverns. By the 20th century, oyster beds were in decline, and stout had given way to pale ale. Ernest Barnes came up with the idea of combining oysters with stout using an oyster concentrate made by Thyrodone Development Ltd. in Bluff, New Zealand, where he was factory manager. It was first sold by the Dunedin Brewery Company in New Zealand in 1938, with the Hammerton Brewery in London, UK, beginning production using the same formula the following year. Hammerton Brewery was re-established in 2014 and is once again brewing an oyster stout. Modern oyster stouts may be made with a handful of oysters in the barrel, hence the warning by one establishment, the Porterhouse Brewery in Dublin, that their award-winning Oyster Stout was not suitable for vegetarians. Others, such as Marston's Oyster Stout, use the name with the implication that the beer would be suitable for drinking with oysters. Chocolate stout Chocolate stout is a name brewers sometimes give to certain stouts having a noticeable dark chocolate flavour through the use of darker, more aromatic malt; particularly chocolate malt—a malt that has been roasted or kilned until it acquires a chocolate colour. Sometimes, as with Muskoka Brewery's Double Chocolate Cranberry Stout, Young's Double Chocolate Stout, and Rogue Brewery's Chocolate Stout, the beers are also brewed with a small amount of chocolate, chocolate flavouring, or cacao nibs. Imperial stout Imperial stout, also known as "Russian Imperial stout", is a strong dark beer