Brian Quail points out that many of those who voted for the Union were bribed (Letters, March 13).

True. He also says that Daniel Defoe, novelist and economic journalist as well as a spy, thought that the Union had not improved the Scottish economy.

He failed to mention that Defoe also said: "Glasgow is a city of business; here is the face of trade; and, I may say, 'tis the only city in Scotland, at this time, that apparently encreases and improves in both. The Union has answer'd its end to them more than to any other part of Scotland, for their trade is new form'd by it; and, as the Union open'd the door to the Scots in our American colonies, the Glasgow merchants presently fell in with the opportunity."

Furthermore, Defoe's tour happened at more or less the same time as the Government set up the Board of Trustees for Fisheries and Manufactures, an early model of Scottish Enterprise, following the Malt Tax Riot of 1725. This board developed the linen industry so successfully that it was used as a model for the cotton industry which established the west of Scotland as one of the motors of the industrial revolution.

It is also worth noting that, although the people of Glasgow and Edinburgh were against the Union in 1707, when an opportunity came to reverse it in 1745 the citizens of both cities backed the Union government. This mood and the increasing prosperity of Scotland in the early decades of Union have been attributed to stable government from afar. Indeed, Scotland's history prior to Union was marked by squabbles between Gael and Lowlander, between great families and between Calvinists and others. The great achievement of Union was to provide stability so that Scotland could produce the Enlightenment (even so David Hume was tried for heresy) and contribute in a major way to the industrial revolution.

History cannot provide the answer to whether Scotland should try independence. But it does point to relevant questions, such as who are the Scots and is there a sense of commonality among them? Have the divisions that plagued its history before Union now disappeared? Or are there new ones?

Many consider the economy to be the most decisive factor in making their decision. On that score we have done well; 1707 was poor and impoverished further by the Darien Scheme; now we are the third most prosperous region in the UK only behind London and the south-east.

The key question is how we would react to adversity. Would we pull together or resume our pre-Union divisiveness?

Michael Boulton-Jones,

5 Glassford Street, Milngavie.

Is the Lord Fraser of Carmyllie who envisages a future scenario in which English aircraft "bomb the hell" out of Glasgow and Edinburgh airports by any chance the same Lord Fraser of Carmyllie who last year was appointed by Alex Salmond as an adviser to the Scottish Government on standards of ministerial conduct ("English 'would bomb our airports'", The Herald, March 13 & Letters, March 14)?

And could he be the same Lord Fraser of Carmyllie who as Lord Advocate drew up the indictment against Abdelbaset Ali Mohmed al Megrahi for the Lockerbie bombing, was satisfied by the verdict against Megrahi, yet subsequently described the Crown's key witness, without whose evidence Megrahi could not have been found guilty, as "not quite the full shilling" and "an apple short of a picnic"?

And can we take anything said by Lord Fraser of Carmyllie with any degree of seriousness?

James Robertson,

24 South Street, Newtyle, Angus.

First we were told that if we voted for an independent Scotland then Edinburgh's pandas would be repatriated to China. Now Lord Fraser of Carmyllie tells us that England is contemplating bombing our airports in the event of foreign threat.

I sincerely hope the Yes campaign is up to the task of countering such awesome arguments for the continuation of the union.

Dr Kevin C Duff,

20 Redwell Place, Alloa.

Who exactly is going to invade Scotland? I do not see any invasion being launched against Iceland, the Faroe Islands or Greenland, which are virtually unprotected militarily.

The suggestion seems to be that an unidentified "enemy commander" would use Glasgow and Edinburgh airports as a launch pad to attack England, thereby forcing England "to come and bomb the hell out of Glasgow airport and Edinburgh airport".

Why would these invaders not use English airports? Lord Fraser's solution to the problem of Trident is breathtaking; relocate it to Scapa Flow. For the noble lord's information, the Orkney Islands are part of Scotland.

The Unionists are clearly desperate but Lord Fraser is simply delivering more votes for independence.

Gordon Bishop,

Summerston Cottage,

2142 Balmore Road,

Glasgow.

I could not agree more with Iain AD Mann on his sensible and logical views on the way to conduct a two-stage referendum (Letters, March 12). My only fear is that none of our politicians will adopt such pragmatism.

A Baillie,

1 Strathmiglo Place, Falkirk.