1. Red. 2. Blue. 3. White over red, two horizontal stripes. 4. The same inverted. 5. Blue over yellow, two horizontal stripes. 6. The same inverted. 7. Union. 8. Blue, white, red, horizontally.
Stars are placed in the four squares whose flags would be one of the invertible flags over its own inversion, probably because there was only one flag supplied of each design, and the other squares are numbered 1 to 68. Sixty-one signals are given. We then have half a dozen signals with Jacks, Pendants, and Wefts, Signals for each point of the compass, ending with 11 pages of Night signals.
Perhaps the best testimony of the value of this book is given in the letter from Nelson to Howe in acknowledgment of his congratulations on the victory of the Nile:
It was only this moment that I had the invaluable approbation of the great, the immortal Earl Howe, an honour the most flattering a Sea-Officer could receive, as it comes from the first and greatest Sea-Officer the world has ever produced. I had the happiness to command a Band of Brothers; therefore night was to my advantage. Each knew his duty, and I was sure each would feel for a French ship. By attacking the enemy's van and centre, the wind blowing directly along their Line, I was enabled to throw what force I pleased on a few Ships. This plan my friends conceived by the signals (for which we are principally if not entirely indebted to your Lordship) and we always kept a superior force to the enemy[387].
Meanwhile, John McArthur, a purser in the navy, who had during the war of American Independence been frequently stationed to observe signals in the fleet and had therefore practical experience of the delays, difficulties and misunderstandings that occurred with the older methods of signalling by flags in particular positions, had been for many years at work on a new code which he submitted to the Admiralty in 1790. The basis of this plan was the old tabular system with two flags hoisted together or separately at the most conspicuous parts of the ship. The code contained upwards of 550 signals, with provision for an indefinite increase, and incorporated an ingenious device for continuously altering the numerical value of the flags. It was an advance upon any of the codes hitherto in use, but "some scruples of delicacy intervened in the adoption of any new plan of signals which would supersede that of Earl Howe's numerary code," and it was not adopted. Nevertheless, it attracted the attention of Hood, then the Senior Sea Lord, and on his appointment to command the Russian armament in 1791 he made McArthur his secretary. McArthur then turned his attention to re-arranging Howe's signals "by simplifying the form with Indices for facilitating their being made and understood, and engrafting in the body and instructions many new ideas and instructions of his own." Howe approved of the alterations, and the revised code was then printed and issued to Hood's fleet. This "new arrangement" was introduced by Hood in 1793 into the Mediterranean and continued to be used there until 1799. It was the signal book in use at the Battles of St Vincent and the Nile. In it the values of Howe's numeral flags, as shown in Col. 1 of Plate XIII, were transposed as follows: 1 became 4; 2, 9; 3, 7; 4, 2; 5, 6; 6, 0; 7, 8; 8, 5; 9, 3; and 0, 1. The tabular flags were also transposed, 1 becoming 8; 2, 7; 3, 5; 5, 3; 6, 2; 7, 1; 8, 6; while 4 remained of the same value.