wooden pole would have had to have been"T^o teet nigh to reach from the
ground to just the base of the cupola, and almost 300 feet high to reach its
But most perplexing is how the cord was fixed at the dome^s centre. A top. The average height of a mainmast for a ship in the British Navy during the eighteenth century was 120 feet, and such masts could be built
only with wood from the forests of the New World — Quebec, Maine and
New Hampshire — since no trees of sufficient height were to be found
anywhere in Europe. As one commentator has observed, 'One would have
to fantasise an enormous trunk of a California sequoia hoisted onto a
central tower or suspended platforms'.^