Tyrian purple 520 nm, which is green). It is believed that the intensity of the purple hue improved rather than faded as the dyed cloth aged. Vitruvius mentions the production of Tyrian purple from shellfish. In his "History of Animals", Aristotle described the shellfish from which Tyrian purple was obtained and the process of extracting the tissue that produced the dye. Pliny the Elder described the production of Tyrian purple in his "Natural History": The most favourable season for taking these [shellfish] is after the rising of the Dog-star, or else before spring; for when they have once discharged their waxy secretion,
Trooping the Colour year emphasise the Queen's knowledge of the attributes of her guards, and single out "steadiness" as a highly prized quality for a guardsman. The accompanying marches always carry a flavour of the regiment whose colour is being trooped, lending the royal inspection a unique atmosphere. For example, if the Welsh Guards are trooping their colour, the music will include their traditional regimental march, "Men of Harlech". While the Queen passes the six companies of foot guards on her left, a slow march or air is played. Once the phaeton turns around the rear of No. 6 Guard, the music changes