Mr. William Sugg, in his regulator or governor, adopts an entirely different arrangement to the foregoing. The valve is placed at the inlet of the governor; and not at its outlet, as in the instrument just described. Instead of a metal bell, a diaphragm of thin and very flexible leather is employed, which is raised by the pressure of the entering gas, and, in turn, actuates the valve; closing the entrance to the governor in proportion to the pressure of gas acting upon it. The orifice communicating between the under and the upper side of the leather diaphragm is controlled by a screw, whereby the quantity of gas delivered to the burner can be regulated according to requirements; but when once it has been adjusted to give any desired pressure of gas at the burner, this pressure will be strictly maintained, no matter with what excess of pressure (within reasonable limits) the gas may be supplied to the instrument. The improved "London" Argands produced by Mr. Sugg (the details of the construction of which have been already described) are too delicately adjusted to be applied with advantage directly to the ordinary consumer's gas-fittings, or wherever any variation in the pressure of the gas supply is likely to be experienced. However, with the addition to them of the above governor, their use becomes as easy and simple as that of other burners; and thus the gas consumer is enabled to obtain the benefit of the most improved apparatus without being called upon to exercise the constant care and attention which, without the aid of the governor, would be necessitated. Besides being applied to Argands, this governor is successfully applied by its inventor to his flat-flame burners. In conjunction with a simple steatite burner of the latter class, it has received a very extended application, under the name of the Christiania governor-burner. [Sidenote: Sugg's Steatite-float governor-burner.]