When I returned to the United Kingdom in the '80's, I joined a company that cut bricks and blocks into special shapes for inclusion into whatever building projects, such as houses or factories, that required them.

Amongst the many specials that were available were tapered arch bricks or voussoirs.  These bricks might require a number of cuts to bring them to the required shape and it always irked me that a certain amount of unnecessary time was spent in working out the calculations prior to carrying out the actual cutting. Because of this, I decided to write a programme that would work out all the necessary dimensions after inputting the required data.  The four features that I was primarily concerned with were Bullseye Windows, Semicircular, Flat Gauge and Segmental Arches and the programme that I wrote concerns the first two which will be available (sometime!!) to download as freeware.  It's called VOUSSOIR, works in Dos and, once again, I used the KISS principal when coding it.  I'm sure that there are other programmes that work out these calculations and I have no doubt that they're very good but please try out mine.  It's an alternative, it's simple to use and it really works.

I am presently working on a programme that will take care of the Flat and Segmental Arches and ultimately plan on combining all four in one programme using Visual Basic - if I can find the time.