Abstract: A method of producing .beta.-form thiamine hydrochloride crystals which comprises moistening .alpha.-form thiamine hydrochloride crystals in the presence of .beta.-form thiamine hydrochloride crystals as seed crystals and stirring the mixture and a method of producing pharmaceutical preparations containing .beta.-form thiamine hydrochloride crystals which comprises moistening .alpha.-form thiamine hydrochloride crystals, together with a binder, with water in the presence of .beta.-form thiamine hydrochloride crystals as seed crystals and stirring the mixture..beta.-Form thiamine hydrochloride crystals which are stable and resistant to caking and pharmaceutical preparations containing the same can be produced in a simple and easy manner.

Abstract: A powder compacting machine for compressing a mass of powdery material to produce substantially flaky articles of substantially uniform thickness is constituted by a hopper unit having a built-in screw feeder and a pair of opposed compressing rolls. One of the compressing rolls is supported for movement close to and away from the other of the compressing rolls. The hopper unit has a hopper, which may be connected to a source of vacuum, and, on the other hand, one of the compressing rolls has a shape complementary to the other of the compressing rolls so that a substantially uniform thickness of the flaky articles made by compressing a mass of powdery material can be obtained. The machine also has at least one barrier employed to substantially uniformly dispense a mass of powdery material falling towards a clearance between the compressing rolls.