The Mechanical Hall (sometimes called the Machinery Hall) was built in 1889 by the Pittsburgh Exposition Society. The contract to build it was awarded in May 1889 on the condition that it would be finished by September, for a cost of $130,000. In 1890 it was the venue for the second Scotch-Irish Congress, building on the popularity of the first one which had been held the year before in Columbia, Tennessee.
If Columbia had typified small-town gentrified Southern charm, all historical white columns and large leafy gardens, the city of Pittsburgh was the opposite in every imaginable way - the biggest steel production region in the world, and North of the Mason-Dixon Line, and the vast building little over six months old right beside the railway line. Pittsburgh was in the top ten biggest cities in America at the time, with a population of around 300,000.
The capacity of the Mechanical Hall was 6000, and 12,000 people showed up, as did President Benjamin Harrison. Professor McCloskie of Princeton declared that "Pittsburg was essentially a big Scotch-Irish city".
Another success, and momentum now gathering around the Society. You can’t help but look back and imagine that this was an America on the edge of a new century, on the brink of becoming a world power, with huge new waves of immigration lapping its shores. Perhaps, faced with the inevitable changes ahead, the fresh interest in Scotch-Irishness was about looking back, to re-root the attendees in a sense of who they were and where they had come from, of heroic deeds and time-honoured traditions and values which in their view had made their America great.