Early trebuchets were built on site. As they grew increasingly large and powerful, wagons carrying sections of prefabricated trebuchets were brought to a siege and assembled in situ.

A trebuchet was a medieval siege weapon, operated using a counterweight to propel a long arm, attached to a sling, which could hurl a projectile with great force and accuracy at enemy fortifications.

Invented in China in around the fourth century BC, by the 12thcentury, improved counterweight trebuchets were in use in Europe.

Historian Michael S. Fulton offered the best examination of the machines in his book Development Of Prefabricated Artillery During The Crusades (2015).

He concluded that while smaller weapons were built on site, large trebuchets were not only assembled but also disassembled afterwards for transport so they could be reused at later sieges.

Perhaps the largest and most famous trebuchet of them all was Edward I’s Warwolf.

In 1304, he ordered his engineers to build this great piece of artillery for the siege of Stirling Castle in Scotland.

Assembled by five master carpenters and 49 labourers, the Warwolf could hurl rocks weighing as much as 300lb.

Early trebuchets were brought on site. As they grew larger and more powerful, wagons carried prefabricated section to a siege and assembled in situ

The Scots, watching the Warwolf being assembled, offered to surrender, but Edward reputedly refused to let anyone leave the castle until the great engine had bombarded it, which it did, successfully levelling the curtain wall.

Jon Francis, Norwich, Norfolk

QUESTION: What did the Keeper of the King’s Conscience do?

The Keeper of the King’s Conscience was a role of the Lord Chancellor. Historically, the Lord Chancellor was head of the Chancery, a court of equity (using fairness to resolve disputes) that originated in medieval England.

In its earliest form, those who were unable to obtain an adequate common law remedy (law derived from judicial decision), or felt they had been treated unfairly, could petition the King of England directly. Rather than making the judgment himself, he would refer the case to his ‘Conscience’, i.e. the Lord Chancellor.

Up until the Reformation the Chancellors were almost always churchmen, versed in civil and canon law. The Chancellor could thus bring legal and spiritual judgment to bear upon the case.Afterwards, the Chancellors were usually trained lawyers used to the process of reasoning.

Sarah Westwood, Birmingham

QUESTION: Was Gustav Holst the first composer to write about the planets?

Before Holst, there were works that explored celestial or planetary themes, though not in such a thorough or systematic manner as The Planets (1914-1917).

Orlando di Lasso (c.1532-1594) was a Catholic composer born in Mons in the Habsburg Netherlands (modern-day Belgium).

While many classical pieces explored celestrial or planetary themes before Holst (pictured), few were as thorough or systematic as The Planets

One of the most prolific, versatile and universal composers of the Renaissance, Lasso wrote more than 2,000 songs in Latin, French, Italian and German. Among his works was In Me Transierunt Irae Tuae (Your Wrath Swept Over Me), which directly inspired the German mathematician Johannes Kepler (1571-1630) to write Harmonices Mundi (Harmonies Of The World).

Harmonices Mundi captured the Pythagorean idea of planetary motion and the ‘music of the spheres’: the philosophical concept that celestial bodies such as the Sun, the Moon and the planets form music as they move through the solar system.

Austrian composer Joseph Haydn’s great oratorio The Creation (1798) celebrated the formation of the Universe. Although the lyrics were based on the biblical books of Genesis and Psalms, and John Milton’s Paradise Lost, Haydn was intensely interested in the astronomical discoveries of the day.

He is believed to have read Immanuel Kant’s Universal Natural History And Theory Of The Heavens (1755), which introduced Nebular Theory, the idea that the planets coalesced from gas and dust orbiting the Sun. The theory, as refined by French mathematician Pierre-Simon Laplace in the 1790s, was popular in the intellectual salons of the era.

Haydn also visited William Herschel’s astronomical observatory in Slough in June 1792. Peering through Herschel’s 40ft telescope may have provided the cosmic inspiration for The Representation of Chaos, the famous opening of The Creation.

It brilliantly captures the formation of celestial spheres from chaos, and it is clear from Haydn’s sketches that he took unprecedented pains over this composition.

Dr Ken Bristow, Glasgow

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