... a socially-prominent woman wrote to a friend, mentioning a public outcry over the cutting of some large trees for the sake of a great project. The protesters won, and the project had to accommodate the trees at great expense, rather than cut them down.

This is the first recorded case of a 'tree-huggers' protest.

What was the great project, and what was the year?

Okay, hint, clues --

There was a crystal fountain --

The admission tickets cost five shillings -- 2 1/2 days' pay for a butler, six days' pay for a lady's maid --

There was a huge diamond on display, worth a million pounds --

This sounds like the Great Exhibition in 1851. It was opened on the Ist of May but the lady could have been writing a few days later or, of course, the year before.

Right again! Damn, you're good! Yes, Jane Welsh Carlyle (Mrs. Thomas) was writing to a friend, describing her recent visit to the Ex. Three large trees had to be included inside the glass because of a public outcry over the plans to cut them down.

Sparrows flying around inside the 'Crystal Palace', the great exhibition hall, presented a bigger problem than trees. What famously terse advice did the Duke of Wellington give?

"Sparrow-hawks, ma'am."