Great Britain's Patent Office
Patent Office of Great Britain, founded 1852. Publications in the mid-nineteenth century refer to an "Office of the Commissioners of Patents for Inventions", Southampton Buildings, Chancery Lane and High Holborn.
British Library can help search for patents up to 1899: https://www.bl.uk/help/find-early-british-patents
According to the Preface to Brewer and Alexander, 1893, Aeronautics:
In the yearly indexes published by H.M. Patent Office, many inventions are included under the heading "Aëronautics" which do not particularly refer to the subject. This error in the official indexes is partly the fault of inventors who wish to cover an enormous ground under one Patent.
The British patent office allowed the filing preliminary patents followed later by "full specifications". Applicants chose this route only sometimes. In espacenet records the full specification, if it exists, usually follows the preliminary record. Dates are given for each filing.
(In 1991 the agency changed its name from "The Patent Office" to "The Intellectual Property Office".)
The patents are classified with a number and year, which corresponds to the time of application. Sometimes in patents these are written as #####/YY; for example Patent GB-1897-10811 can be written 10811/97 (and using the same two-digit system after the turn of the century; see Patent GB-1913-22125.)
If you know the year and number of a patent you can search for it on espacenet as per the following example:
The number following the year must always be five digits; use one or more zeroes if the number is less than 10000.
British patent application numbers from 1852 and 1915 began with number 1 each year.
National tech classification
While British patents do not (like French and German patents) bear a classification directly on the original document, they did receive contemporary classifications, after a slight lag. These can be seen in the division of volumes and then sub-indexing in the Abridgment of patent specifications which began coming out in the 1860s (and covered patents going back to 1617). From 1884 there was a separate primary class (number 4) for aeronautics.
The edition for 1893–96, published in 1899 has about twenty subclassifications within "Aeronautics", including "aërial machines without aërostats", "aëroplanes and the like", "framework", "military apparatus", and "shock of landing, deadening", followed by the numbers of patents within these categories in this time period.
- In related working paper "Necessity is the Mother of Invention: Input Supplies and Directed Technical Change", W. Walter Hanlon wrote (p48): "I constructed a database covering all of the patents granted in Britain between 1855 and 1883, 118,863 in all. Each patent is classified into one or more of 146 technology categories by the British Patent Office (BPO)."
As the number of patents increased so did the number of classifications and internal subdivisions. See for example the splitting and heavy subdivision of GB 4 propel & steer.
Several British patent agents also had addresses in "Southampton Buildings" and on Chancery Lane.
Historical development of the system
In the middle nineteenth century the British system evidently worked a little differently. More facsimiles of early patents have been made available online in recent years and we are beginning to work through these. A number of patents received ordinal numbers but only received "provisional" protection; others were "Sealed", i.e. made official, and the sealing date is given along with the filing date at the beginning of the document. It may be that the Sealing process involved multiple steps, and further consideration is needed for us to decide whether the given Sealing date is analogous to the Grant date.
Provisional specifications were generally shorter and sometimes supplanted by lengthier versions at "Sealing" — but the length of patents varied greatly across the board. It seems provisional specifications were usually not accompanied by illustrations.
An important legal change occurred with the Patents Act of 1902.
- cite state library of Victoria for this sentence
- Find early British patents at British Library site; it says: The British Library has the national collection of British patents and associated documentation. This guide . . . covers the period 1617 to 1899.
- British patents at the British Library -- lists categories of patent-related documentation available at the British Library physically. It seems feasible to go there and get access to the ones in the early aero period.
-  - British patent info from the State Library of Victoria, Australia
- Search for Australian patents from 1904 on. Before that, there was no Australian system and Australians filed generally in the British system.
-  - guide to Australian patents
- Structured search of Australian patent -- this one may be most efficient for earlier ones ; I couldn't get the general/easy search to find them
- use advanced search or follow advice here for pre-1920 Australian patents: https://guides.slv.vic.gov.au/patents/Australia
- if one knows the number, and construct a six-digit zero prefixed version of the number, and you know the year, a format like this will work: http://pericles.ipaustralia.gov.au/ols/auspat/applicationDetails.do?applicationNo=1912006224
- more sources, undigested
- Australian patent user guide - long pdf