I acquired this at an auction knowing really very little about it.  It's called the Decca and was made by "The Dulcephone Company", the bowl reflex system being called the "Dulciflex". The Dulcephone Co. had produced one of the first truly portable gramophones, the design being patented under the number 3033 in 1914.  This style of portable became popular with soldiers during World War 1 hence earning it the name "Trench".  The model 1A appeared in 1921 and was a halfway stage between the Decca Models 1 and 2 having the "Dulciflex sysytem and a dark green, often thought to be black, case.  In fact it was only when I got it home and cleaned it that I realised the case was green having been described by the auction house as black. The apparent simplicity of the arm joint conceales a rather sophisticated playing weight adjustment, details of which I have shown in the photos as many owners of these machines are not aware it's there!