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Looking at these instruments the distinguishing features are:
They are flat pattern and similar in general dimensions to Richter instruments
They are made of electrum (nickel silver)
They have a special head design (Fig 3) that separates the two mating faces of the legs with a steel washer and has conical steel pivots between the head forks and the legs. It is not self-centring. It is basically a copy of the design used by Kern of Aarau, Switzerland.
The lead holder is the collet type
The needles are held by a nut and bolt that is a derivative of Stanley’s original design, sometimes called “type B”, that he patented in 1863iii. The needle leg of the compass is jointed near the needle end as are the needle legs of the ink and pencil bows. The needle legs of the dividers are also often jointed in this manner but some are not jointed.
The dividers and the large compass usually, but not always, have hair adjustment. However each maker uses his own design for this feature and it is not standardised.
The pens and pen inserts usually hinge open for cleaning but some have spring nibs.
The compass inserts are generally interchangeable between manufacturers so the spigot and socket are standardised. However screw threads are not necessarily so although they are presumably all BA.
The compass does not have an extension bar
This paper was previously published in the Bulletin of the Scientific Instrument Society No.128, March 2016
The story begins, not in England, but in Germany. Historically, drawing instruments had been hand-made and were heavy and expensive to produce. When parts were damaged or lost there were, in most cases, no spares available to repair the instrument. The first firms to address all of these issues were both German, namely Clemens Riefler with their round system, and E O Richter with their flat system, the latter being patented in  1892 and it is this system that is the starting point for the British Empire pattern.
Prior to the First World War all the British makers of drawing instruments continued to produce the heavy English pattern, largely by hand although W F Stanley had mechanised parts of the process and achieved interchangeability of parts. These sets were expensive and there was a need for cheaper instruments that would still produce good work and last a lifetime. Some of the makers therefore started importing the German instruments to supplement their own production. One such firm was A G Thornton and I have an example in my collection. (Figs 1a & 1b)
Fig.1 (a) An E O Richter set sold by A G Thornton ca.1910, and (b) the A G Thornton name on the otherwise normal E O Richter pin-lock case
The Influence of War
With the onset of World War I several factors would have come to bear:
The need for drawing instruments would have increased to meet the needs of new equipment design for  the increasingly mechanised armed forces
Skilled labour would have been lost to the armed forces
Materials would be in short supply
It would no longer be possible to import instruments from Germany
Manufacturing came under government control
From the firm’s 1916 cataloguei, it is clear that they continued importing Richter instruments until the onset of war and presumably continued to sell them until stocks were exhausted. However they introduced the brand name “Minerva” about this time for flat pattern instruments. This was to become their best selling brand for flat pattern instruments of their own manufacture until well after World War II and these were also sold under different brand names by several other ‘manufacturers’.
With the industry under government control both an opportunity and a need for standardisation existed. As a result a government standardii for flat pattern drawing instruments was created, which subsequently became known as the British Empire or BE pattern. As will become evident when we look at some of the sets, it appears to have been an incomplete standard or limited standard as there does not seem to have been any standardisation of spring bows. Although there were more suppliers, some of whom claimed the instruments as their own, there appear to have only been three actual manufacturers of this pattern, namely W F Stanley & Co Ltd, A G Thornton Ltd and W H Harling Ltd.
The Instruments Included in the Standard
Fig.2 A selection of Government Standard instruments. From left to right, Stanley 1919 compass, Thornton 1939 compass, Harling 1937 compass + inserts, Stanley 1919 dividers, Harling 1937 dividers (shown upside down to show the unusual hair adjustment lever that required the head design to be modified), Thornton 1939 dividers, Stanley 1919 ink & pencil bow compasses. Note the hair adjustment for the dividers is different for each maker and that this feature is present on only some of the compasses. Each Stanley instrument has an individual serial number.
Fig.4(a) The principal instruments were placed in the lift out tray of the standard case; (b) the base of a Thornton case showing the proprietary “Minerva” series spring bows Each maker inserted their own proprietary instruments as these presumably were not part of the standard; and (c) the space in the lid for the rectangular protractor and parallel rule
Between the wars many of the instruments were provided in a standard wood case (Figs 4a, 4b & 4c). This case appears to have already been in existence when the drawing instrument standard was produced as sets of English pattern instruments are also found in it that predate the new standard. This case seems not to have been on general sale as it does not appear in any of the manufacturers’ catalogues. All the cases I have seen have the broad arrow mark on the instruments inside and the case, and are dated. However all the makers catalogued and sold the instruments individually, and in cases of their proprietary designs, to the public as well. W H Harling at least also sold them to other firms for sale to the publiciv. Whilst some of these firms may have made their own English pattern instruments, they could not afford the investment in the machinery needed to produce high quality flat pattern ones.

The Cases
Let’s deviate from the instruments themselves to the standard cases. They are generally made of mahogany and have a lift out tray and a hinged lid lining. They measure 8½ x 4¼ x 2 inches and have a very distinctive brass catch (Fig 5). The tray contains the following items in fitted, velvet lined pockets:
Six inch compass with pen, pencil and divider inserts
Six inch dividers
Pen and pencil bow compasses
Six inch and five inch ruling pens
A compass key and a container for spare leads
The base is divided into three sections. All are velvet lined. One contains three spring bows (pen, pencil and divider). One contains a sheet of cork for holding drawing pins. One is provided for holding pencils, etc.
The silk lining of the lid hinges up to reveal a rectangular protractor and a six inch parallel rule.
Some smaller sets were also supplied to the government, typically in black leatherette covered pocket cases.
Fig.6 A top of the range Harling BE112 “British Empire Pattern” set based around the government standard instruments. It dates from 1935. Wallet cases were pretty much the Harling standard at this time.
Fig.7 A small Harling “Technical Series” set from the 1930s. The compass is a small size one but has the government standard type of head joint.
Commercial Production
All three firms also produced these instruments commercially. W H Harling made these their standard professional flat pattern series and called them “British Empire” series (Fig 6). They had a very long production run. They also produced a “Technical Series” (Fig 7) closely based on the BE one and these were still available as late as 1970. The Harling British Empire series adhered closely to the standard but stainless steel was normal for the pens and other steel parts. They also added a straightening device (an adaptation of the central washer) to the heads of the compasses and dividers. They also introduced an extension bar for the compass.
Fig.8 A Thornton Minerva set, probably from the 1930s, in a typical Thornton case. The design of the instruments is quite similar to the Richter instruments they sold up to WWI.
A G Thornton produced them as their BE series. However Thornton’s biggest selling professional type was their “Minerva Series” (Fig 8). The inserts for the BE series and Minerva series are interchangeable as also are those of the cheaper “Techset” series although the materials and construction sometimes differ. The Minerva series was cheaper to produce and hence sold at a slightly lower price; consequently it appears it became the best selling, British made, professional quality, flat pattern series. Thornton did produce for a time in the 1930s a variant of the BE pattern with their Minerva ball bearing head (Norton & Gregory patent 207383/22). Later Thornton patented their own design of ball bearing head used on some post WWII Minerva series instruments (GB684,850).
Fig.9 A Stanley “Government Pattern” set in a Perma case dating from 1937.
W F Stanley also produced the type commercially but merely called it “Stanley’s Government Standard Pattern”. They too added an extension bar for the compass and a self-centring device for the head, the latter similar to that used by Harling. Also stainless steel became the norm for the highest quality. Many of these sets were sold in their new Perma cases (Fig 9). Examining a 1937 example in my collection shows that the shape of the compass legs has changed and the inserts are no longer interchangeable with those in sets produced for the government.

World War II
It seems that purchase of the standard pattern of drawing instrument in the standard case described earlier by the British government ended sometime during the course of WWII. The instruments were high quality and relatively expensive to produce. Shortages of materials and other things led inevitably to economies having to be made. Unfortunately, except for compasses made to an Air Ministry requirement and very varied in design, I have not come across any dated WWII period drawing instruments. However at some stage a new type of set emerged to meet the same requirements but much less standardised, of cheaper construction, and in a differently shaped case (Figs 10a & 10b).
Fig.10(a) The revised style of standard case, in this instance a J J Threadwell one, and (b) the tray of instruments in the Threadwell case. Note that the dividers are chrome plated brass whilst the other instruments are electrum. I have other ‘austerity’ period Threadwell compasses that even have parts made of electrum and other parts of the same instrument made of brass, presumably due to material shortages. In spite of these material variations Threadwell instruments were very well made and better than the instruments made by other makers found in these government standard cases
The case contents and layout are basically the same as that described earlier but the instruments are now proprietary designs, sometimes simplified, and using the materials available such as plain or plated brass. The case catch is now a typical commercial product and one case in my collection (containing instruments made by BWC, whoever they were) is actually made of beech. The manufacturers of these sets include A G Thornton, J J Threadwell, BWC and WEDOCO (another firm I haven’t been able to identify). None of these sets is dated so they could have been made during or after WWII. Only the Thornton and Threadwell sets have clear evidence they were made for the government. The Thornton instruments are brass, the Threadwell ones are a mixture of electrum and plated brass, the BWC ones are plated brass and the WEDOCO ones from memory were plated brass (I don’t have this set in my collection but have a civilian set with similar instruments). Both BWC and WEDOCO seem to have flourished as drawing instrument makers for a short while and then disappeared into obscurity, which is not surprising as the design and manufacture of their instruments fell well short of that of the leading makers. J J Threadwell are not well known because their instruments and sets are rarely signed but they made high quality instruments for other firms including Charles Baker, W F Stanley, and Cooke, Troughton & Simms.

Return to Normality
By the 1950s Government purchasing policy appears to have changed back to high quality instruments and the Government Standard Pattern is again purchased. W H Harling appear to be the main, possibly sole, supplier of these. They are now supplied in leatherette covered cases and I have examples made for the Hydrographic Office and the army. The latter (Fig 11), coded W10/VC/5841 is dated 1953. The contents of that one are basically the same as those of the 1930s sets and the parts are still interchangeable with those.
Fig.11 The Harling W10/VC/5841 case dated 1953. There are a rectangular protractor and parallel rule housed under a flap in the lid.
Fig.12 The “Halden British Made” set
Halden’s British Made
J Halden & Co made a series of flat pattern drawing instruments that embodied many of the features of the British Empire (Government Standard) Pattern, especially the type of head joint and the needle points. Fig 12 shows an example. The inserts are not interchangeable with those of the British Empire Pattern and I don’t have any evidence of them ever being made for the government. I have a somewhat similar set branded HUSUN (Henry Hughes & Son) that I suspect was made for them by Halden as the parts are interchangeable and the compasses have finger recesses that are not present in the pattern made by Harling and others for the government. In 1919 Henry Hughes & Son advertised a similar set as the “British Empire Set” at £2.15s post freev This pattern was very short lived and does not appear in the ca.1926 Halden catalogue, which shows their “Premier” ranges (actually Thornton Minerva and Techset instruments). Halden by then specialised in machines for printing copies of drawings for which they obtained many UK and French patents.

Influenced by the First World War a standard for drawing instruments was produced for the British government by an inter-departmental committee. The standard was for high quality, flat pattern instruments but was very limited in its scope covering only the compass, divider and bow compasses. Interchangeability was a key requirement. Some aspects of the design appear to have been left to the manufacturer. Most of the sets made for the government were housed in a standard case of a type that was not sold commercially. There were three makers, Stanley, Harling and Thornton.
The instruments were also sold commercially and one maker, Harling, made these its premier product line and also made them for other firms. Commercial variants were also designed and made. Halden made their own, short-lived, version of the standard pattern, not interchangeable and not procured by the government, that was also sold by Henry Hughes & Son.
Some time in the 1940s production of these standard instruments for the government ceased and they were replaced by cheaper, lower quality instruments, housed in a re-modelled case. Some of the manufacturers of these were new to the field and their production was short lived. In the 1950s government procurement reverted to the British Empire pattern but in more basic cases.
Much of this article has been based on circumstantial evidence as the standard has not been traced, the government cases do not appear in makers’ catalogues, and only a few of the instruments are dated. Any information that can help with dates or add to the knowledge will be welcomed.

Notes & references

i) Drawing Surveying & Scientific Instruments and Drawing Office Materials, A G Thornton Ltd, Manchester. Pages 69 and 70 show examples of their “Minerva” Series (Flat Pattern) sets. The illustrations clearly show E O Richter type instruments, possibly old stocks or just old illustrations. Page 38 shows an E O Richter mechanical dotting pen and the illustration has the Richter trade mark shown on the instrument.
ii) This standard is referred to in several manufacturers’ catalogues (e.g. Stanley 1931, Casella ca.1930) but so far I have been unable to find a copy or trace its publication date.
iii) Patent GB1863/226 Mathematical Drawing Instruments covers several improvements and is described in the author’s paper on Stanley instrument patents in SIS Bulletin No 113, June 2012.
iv) Casella Surveying & Drawing Instruments and Appliances catalogue no 564 (ca.1930) pages 173 to 187. “The sets illustrated and described below are all of the new patterns approved by the Inter-Departmental Committee appointed to consider the design of British drawing instruments. These patterns have several important advantages over older British models:-…..”. From detailed examination of the many illustrations it is clear that these were made by W H Harling; they even used Harling engravings with Harling’s name removed and Casella London substituted. The same is also true of A West & Partners, see page 73 et. seq. of their 1930 catalogue.
v) Grace’s Guide British Industrial History, www.gracesguide.co.uk/Henry_Hughes_and_Son
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