From the 17th century maritime trade began to boom in England. Shipowners, merchants and underwriters in the City of London gathered in particular places to exchange news, gossip and intelligence. One of the most popular meeting places for those in the maritime trade was Edward Lloyd’s coffee house, first opened in 1688.
Lists of ships and shipping movements were published intermittently from 1690, with the more uniform and regular Lloyd’s List started in 1734, but there was no information on the condition of those ships. The Society for the Registry of Shipping (which later became Lloyd’s Register) began filling this gap from 1764 when they first published the Register of Ships. Subscriptions to the Register Book paid for surveyors to inspect vessels and give them a rating (or class) which was then recorded in the Register Book for the subscribers’ benefit.
Each ship’s entry included information such as name (and previous names), the master, the port the ship was going from and to, her tonnage, the number of guns she carried (as merchant ships during the period were often heavily armed), where and when she was built, the owners, and the classification the Society’s surveyors had awarded its hull and equipment.
In 1799 disagreement about the classification system led to a group of shipowners splitting off and creating their own Register Book. Their book (known as the Red Book, or Shipowners’ Register) included information such as how a ship was built and her condition. The original book, now known as the Green Book or Underwriters’ Register, instead focused on the age and place of construction of ships.
Subscribers across the country increasingly found problems with the methods of both registers, and in the early 1820s a movement began to develop a new system of classification. In 1834 the two registers were reconstituted as Lloyd’s Register of British and Foreign Shipping and new Rules for Classification were implemented.
Lloyd’s Register has used many notations throughout the centuries to denote classification. In the 1764 Register ships were given a rating of A, E, I, O or U for their hull, and G(ood), M(idling) or B(ad) for their equipment. In 1768, the notations were changed from G, M and B to 1, 2 and 3; A1 was the highest class a vessel could be given. In 1834, with the re-constitution of the Society and Register Book, the possible classes were pared down to A, Æ, E and I (hull) with 1 or 2 (equipment).
In 1853 the Society introduced the Formée Cross (similar in design to the Maltese Cross) to its classification symbols.
As part of a wave of overseas expansion, in 1852 Captain Thomas Menzies and other surveyors were sent out to Canada where they carried out detailed and extensive supervision of shipbuilding. Captain Menzies suggested that ships built under their supervision should be certified as ‘Built under Special Survey’. The General Committee thought this was such a good idea that they decided to apply the practice worldwide, and picked the Maltese Cross design as the symbol they would use.
Over the years the classification system has expanded to adapt to innovations such as iron ships, steam engines and electrical engineering. This image here
shows the notation LMC (Lloyd’s Machinery Certificate), which indicates survey and classification of the ship’s machinery by Lloyd’s Register’s Engineer Surveyors. The numbers following these letters indicate the dates on which items of machinery (usually boilers) were previously surveyed; that is, LMC 1, 51 means the machinery was last surveyed in January 1951.
A black Maltese Cross denotes the ship has been built under Special Survey, while a red Maltese Cross denotes a ship’s engines, boilers, or both, have been built under Special Survey.
Following its origins in a small but lively coffee house in London in 1760, the system of classification underwent fascinating changes in the 18th and 19th centuries. These reflected geographical changes in shipbuilding, innovations in technology and the evolving needs of those involved in the maritime industry.
More information can be found on the Lloyd’s Register Info Sheets (see references below).
 Nigel Watson, Lloyd’s Register: 250 years of service (Lloyd’s Register: Fenchurch Street, 2010), p. 11.
 Watson, Lloyd’s Register, pp. 12-18.
 Lloyd’s Register Foundation, ‘Infosheet No. 42, Classification symbols 1764-1994’, p. 1, http://www.lr.org/en/_images/213-35667_42-class-symbols.pdf; and Lloyd’s Register Foundation, ‘Lloyd’s Register: From Coffee House to Post Modern Building’, p. 3, http://www.lr.org/en/_images/213-35658_31-lloyds-register-pics.pdf
 Lloyd’s Register Foundation, ‘Infosheet No. 36, The Maltese Cross’, http://www.lr.org/en/_images/213-35662_36-maltese-cross.pdf; Watson, Lloyd’s Register, pp. 28, 261, 101.
 Lloyd’s Register Foundation, ‘Infosheet No. 42, Classification symbols 1764-1994’, pp. 1-3, http://www.lr.org/en/_images/213-35667_42-class-symbols.pdf
 Lloyd’s Register Foundation, ‘Infosheet No. 42, Classification symbols 1764-1994’, p. 12, http://www.lr.org/en/_images/213-35667_42-class-symbols.pdf
 Lloyd’s Register Foundation, ‘Infosheet No. 42, Classification symbols 1764-1994’, p. 2, http://www.lr.org/en/_images/213-35667_42-class-symbols.pdf