Hello all, I'm looking for a little info on traditional English slide trumpets. What would have been in popular use in the 19th cen. The main two questions I have is what was the most popular key of the instruments and what notes could they not play. I think I understand they could lower the notes of the overtone series by up to 3 half steps. So what I really need to know is what the fundamental is or just a chart of the notes possible. Thanks in advance if anyone has any information on this.