Chancery: Petty Bag Office: Specification and Surrender Rolls

This series consists of enrolments made up in the Petty Bag Office of specifications of patent inventions and surrenders of office.

Specifications, complete with drawings or sketches, give a description of the patented invention sufficiently full to enable its nature to be understood and applied in practice.

There is a huge range of subjects for patents in this series. Many involve industrial processes, and machinery for industry, and cover areas such as thread spinning, cloth weaving of all types, ironworking and other heavy engineering, railways, shipping, chemicals, paper making, brewing and distilling, refining and drying foodstuffs and oils, filtering and purifying water, and the manufacture of screws, locks, springs, bricks and tiles.

Processes and machinery for the improvement of agricultural methods are also well represented. There are specifications for many items of clothing, hosiery, furniture and furnishings, household articles of many varieties, and improvements to utilities and amenities, such as gas, water and paving.

Also represented are many famous names, particularly industrial engineers such as James Nasmyth, William Congreve, John Heathcoat and William Fairbairn, as well as John Dolland for optical inventions and Joseph and John Manton for gun making.

Certain surrenders of office are enrolled with the specifications, although the reason for this is not clear. They are few in number compared with the specifications, and tend to occur more in the early rolls. Examples of such offices include master in ordinary in the Court of Chancery, baron of the Exchequer, Oxford University professor, and the governor of Alderney.

Other specifications and surrenders are enrolled in C 73

Chancery surrenders of office are also enrolled in C 75

Topics

Clothing

Manufacturing

Railways

Oil and gas

Research

Weapons

Food and drink

Farming

From the late sixteenth century inventors could apply for letters patent granting them, for a period of time, the exclusive right to manufacture their invention. Specifications of inventions began in 1711, and were virtually compulsory (though this was never embodied in any statutory provision) by 1734, when the procedure was standardised. Early specifications were intended mainly to show the confines of the patentee's monopoly rights and the limits of the field in which others were prohibited from entering. The specification was also a test of the novelty of an invention.

Between 1711 and 1734 less than a fifth of grants of patent were followed by a specification, but after 1734 the validity of the patent was made dependent on the lodging within a stated time of a full specification. Enrolment of this specification became the accepted practice, to be submitted either to the Rolls Chapel, the Petty Bag Office or the Enrolment (Six Clerks) Office. This necessity was not greeted with universal enthusiasm. It added both to the time involved in the process, and the cost; the making up of drawings was particularly expensive.

The specifications were regarded as a vital record of scientific and technological progress, and were never closed to public inspection. After 1848 all specifications were to be enrolled at the Enrolment Office on the close rolls, and subsequently in the Office of the Commissioners of Patents. The series of enrolments at the Petty Bag Office thus ceases at this date.