1875 W. & T. Avery Imperial Standard Yard

The 1875 W. & T. Avery Imperial Standard Yard in its original case.
Figure 1: The 1875 W. & T. Avery Imperial Standard Yard in its original case.
On an auction of the Dutch Weights and Measures Collectors Society (GMVV) this Standard Yard came up for sale in 2014. It was offered for sale together with the Standard Inch in the collection. Having already a 66ft Standard Chain in the collection these two standards were the perfect excuse to go to the auction.

This Imperial Standard Yard was made by William & Thomas Avery Ltd., who had their premises in Birmingham from 1817 until 1894, and came complete with its original case.1

A yard is divided into 36 inches and so is this particular one. The divisions can be found along one side of the yard. The first and last inches of them are subdivided into 100 parts, while the second from the left is subdivided into 16 parts and the third from the left into 12 (see figure 9). The other inches are not subdivided.

The ends of the yard have raised blocks to allow any yard to be tested between them (see figure 7). Of correctly made a yard should snugly fit between the blocks.

The right end of the standard yard showing the Indenture Number 1540.
Figure 2: The right end of the standard yard showing the Indenture Number 1540.
As all British standards this yard received its own Indenture Number (see figure 2). The Indenture Numbers are kept on file and allow to trace the history of the corresponding standard. This particular standard yard received Indenture Number 1540, which is stamped on the right block and corresponds with the entry date of 1 February 1875.2 Dating the instrument with the Indenture Number would be no problem as the year is engraved with large figures at the centre of the yard, next to the intended owner, the Borough of Batley.

Both ends of the yard bear Victorian hallmarks. Spread among the ends are hallmarks of 1891, 1909, 1920, 1930 and 1940, stamped above portcullises. Next to them are crowned hallmarks for Edward VII and George V (see figure 2 and figure 8).

The yard is made of brass and nicely engraved with the texts "Imperial Yard" (see figure 5), "Borough of Batley, 1875" (see figure 4) and "W.&T. Avery, Birmingham" (see figure 6). It came with its original mahogany case which, like the instrument itself, still is in fine condition. On top of the lid a brass plaque is fastened reading "Boro of Batley. Yard Bed." (see figure 10), while on the inside of the case the Indenture Number 1540 can be found in pencil (see figure 4).

Notes

[1]: G. Clifton, Directory of British Scientific Instrument Makers 1550-1851, (London, 1996), p.13.
[2]: Ricketts, C., Marks and Marking of Weights and Measures of the British Isles, (Taunton, 1996), pp.1-16.

If you have any questions and/or remarks please let me know.

The mahogany case of the Imperial Standard Yard.
Figure 3: The mahogany case of the Imperial Standard Yard.
 
The yard was made for the Borough of Batley in 1875, the Indenture Number is visible in the lid.
Figure 4: The yard was made for the Borough of Batley in 1875, the Indenture Number is visible in the lid.

This is an Imperial Yard.
Figure 5: This is an Imperial Yard.
 
The Standard Yard was made by W.&T. Avery Ltd. in Birmingham.
Figure 6: The Standard Yard was made by W.&T. Avery Ltd. in Birmingham.

One of the end blocks of the yard.
Figure 7: One of the end blocks of the yard.
 
The other end block with hallmarks and the first inch divided in 100 parts.
Figure 8: The other end block with hallmarks and the first inch divided in 100 parts.

The start of the yard with three differently divided inches.
Figure 9: The start of the yard with three differently divided inches.
 
The Boro of Batley label on the case.
Figure 10: The Boro of Batley label on the case.

Surveyor's crosses Geodetic Sextants Theodolites Total Stations Levels Standards Tools Firms
19th c. W&T Avery Ltd. Inch 1875 W&T Avery Ltd. Yard 19th c. Doyle and Son Chain Breithaupt PRURO