Chemical equipment. Early 19th-century artwork depicting a variety of devices and instruments used in chemistry experiments. These include glassware such as flasks and connecting tubes. At upper left is a weight-and-pulley, together with a lens being used to focus sunlight to produce heat. This is Plate III of a series on modern chemical apparatus published in London in 1800 for the 'Encyclopaedia Londinensis, or Universal Dictionary of Arts, Sciences, and Literature'.