Does anyone have any working knowledge of early pneumatic tankers. When did they come into use, what were they like to use,that kind of thing? Must be some good stories/memories amongst the members. 
hi longway,used to drive this tanker for about 10 years in the 70/80s used to get asked to do loads of unoficial jobs with it like cleaning down farmers barn roofs (inside) blowing out there grain store floors, cleaning thier feed hoppers, sweeping our own company yard with about 4 pipes on,lot easier than a brush (was a big yard) and drain cleaning were it excelled. used to blow the tank up to 20lbs pressure put the pipe down the man hole with the cover back on,open the main air valve and retreat to a safe distance because when it went some times every thing with in 20yds got what ever was in the drain/often had to wash it after these jobs. one day at our local mill one of the formen asked me to clear a drain that had been blocked for weeks so put the pipe down as usual but nothing happened for a few minutes so guess what he went for a look down the far drain just as it blew out,his white overalls turned to a sh–y brown. last seen going home to get changed. he was a lovely bloke and when he came back he had a good laugh about it . all this and still managed to deliver 60 tons a day to our local farms. HAPPY DAYS.
Thanks for posting that nice picture.
A few years back when I was doing cement we had this customer who ran a ramshackle concrete yard in Brooklyn.He never maintained anything and the place was a regular obsticle course to back into and get on the silo pipe.There was all manner of broken down equipment scattered about the yard,old mixer trucks and front end loaders that had been taken half apart and never put back together,then left to rot.
Anyway once you were finally backed in place and hooked to the pipe the procedure was to go inside the office and get the okay to start pumping.The old boy would always yell as you were walking away “watch the pressure,no more than 10 pounds”.Well the filters bags were solid concrete because no one ever changed them and more often than not cement would just blow out the top of the silo,covering cars out in the street and agitating the neighbours.
As it happened the office ,gravel conveyors and maintanence shop had been built around and attached to this old silo,it’s top half protruding through their roof. One day one of the hot headed younger drivers had got him’s nickers in a twist with all the backing around obsticles to get on the pipe,it was no easy task, and being his first time there,and being all wound up, he ignored the owners demand for “no more than 10 pound” and proceded to unload at 17psi.
Well no one noticed the silo was not relieving itself by blowing cement out of the top like normal.It had finally sealed up solid with cement,probably because the rain leaked in,and after about 15 minutes of pumping the bottom just blew clean off dumping about 30 tons of cement inside the office and everywhere else. 
Just imagine that dust cloud. 