Below is the DeVlieg/Herbert 1978 catalog for Type H Jigmil, a machine introduced during the late 1970s and built into the 1980s. Not only does it show the specification of the various models but also how they functioned and the accessory range. Type J Jigmils were offered with a number of difference CNC control systems, the first being a design exclusive to the English Herbert Company. For an even fuller explanation of the principles behind the DeVlieg Jigmil - and how they were intended to be operated -  see the comprehensive data on the earlier Type B and the accompanying article here http://www.lathes.co.uk/devlieg