Abraham three draw telescope

Jacob Abraham of Bath is a renowned maker of telescopes, and up until this year I had never been successful in acquiring a sample of his work. He was active between 1809 and 1842, and was sought out as a supplier by the Duke of Gloucester and the Duke of Wellington in that time period.  This model is a three draw unit with a mahogany barrel.

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Admittedly the photos and description on Ebay may have put other buyers off, as all the screws into the wooden barrel were missing, so it was an assembly of loose bits, and the third draw seemed to have an extra brass ring around the circumference.

Close investigation suggested it had had quite a hard working life! But once cleaned up, with the wooden barrel polished and modern screws used to hold the two end pieces into the wood (using 3/8” long screws, cut down to about 5mm), the unit is optically very good. It seems the barrel has been shortened at some point, presumably because the original screws had been pulled out of the wood too often, and there was nothing left to screw into. This then made the largest draw too long to fit into the barrel when closing the scope together, ie it hit the back of the objective lens. So to stop this potential damage the owner, or his staff, soldered a ring of copper (very neatly) around this last draw, which prevents it being pushed fully home into the barrel.

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The added copper ring round the third draw, and new screws in the barrel.

A questionable eyepiece?

The engraving on the first draw is shown below, as well as the soldering holding the eyepiece cap in position.

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As well as this mod on the third draw, the eyepiece cap has been soldered onto the end of the first draw. This cap is not necessarily the original, it may have been added to replace another cap damaged and/or lost. The shape of the cap, in terms of the tapering on the rear side, is just not what was fashionable or normal in the early 1800s. This was also the dubious aspect of a telescope discussed in an earlier story, the 8-draw Ramsden, where a correspondent pointed out that this was a fashionable shape in the  late 1800s, particularly with manufacturers in France.

DSC05531This soldered joint also means the first lens cartridge now seems to be permanently anchored in place, it does not appear to be removable any more.

Total length extended is just over 26”, and 8.75” when closed. The barrel OD is 1.75”. The draw tubes are actually in good condition, with only a few dents, in contrast to the other trauma the telescope has seen. The knurled ring on the fitting to the barrel does appear to have lost a segment of about 10 degrees, but still works fine. The missing segment can be seen on the photo above,  showing the copper ring.

Conclusion

It is still an effective telescope, and from Abraham in Bath, as the engraving says. This is also a useful size for use in today’s world.

It is worth mentioning that there were other instrument makers by the name of Abraham in other towns. For example Abraham Abraham in Liverpool, Abraham Elisha Abraham in Exeter, G & C Abraham in Sheffield, and John Aburgham Abraham also in Liverpool. This Jacob Abraham started in St Andrew’s Terrace in Bath 1809-1811. From 1830-1842 he was at 7 Bartlett Street, Bath, but also opened an office in Cheltenham. From 1833-37 this office moved to be adjoining Mr Thompson’s Pump Room in Bath, presumably to catch all the gentry taking the waters. He also developed partnerships with other instrument sellers, to presumably sell Abraham units, from bases in Glasgow, Liverpool and Manchester.

Accession number #312.

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Medium sized Dollond from 1810

This is a 3-draw Dollond with a wooden barrel, a medium sized telescope around 20” long when extended. It was acquired in August 2017, as ref #313, and is frankly the same as two previous purchases, those with Accession numbers #193 and #98.

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Dollond #313 (bottom) and #98 (top)

 

The design is classic for a medium sized scope, very similar to the early Ramsdens or the Watkins & Hill described on the last page – although earlier than that one, dating from between 1810 and 1820. The major difference in the Dollond is that the lens mounting positions in the first draw are at either end of the draw, and then at two places where the draw is split to allow access to these lenses. The photo shows the lens mounting positions along the first draw:

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At the top are the two mechanical fittings. The first draw is made from the three bits of tube, shown in the middle row. The four lenses are shown as the bottom row, they go inside the ends of the tubing sections.

The reason this design is attractive enough to buy three models is that the Dollond optics are superb. Regrettably for Dollond, the mechanical construction is not so robust: the draw tubes are relatively thin, so examples can have damaged tubes that are difficult to move, and the joints between the tubes are not soldered in place as well as is achieved in later Dollond models, or other supplier’s units. The scope ref #98 had these poor joints, and no eyepiece cap. So it is basically used as a source of spare lenses. Ref #193 was complete, although one draw was stiff and the mahogany had a crack along the length, but it worked beautifully: this one was given away.

Why buy this third model?

Ref #313 was bought to replace #193, and is complete with end cap and slider in the eyepiece, and with original screws in the barrel. The mahogany barrel has a thick layer of French polish over the original polish, and looks almost black. It does have one mechanical problem, the shoulder of the slider on the second draw is only a press fit in place.

DSC05551 mounting ringIt is interesting to note that the design of this slider and shoulder was a Dollond Patent as well, described first in around 1780 apparently! It follows good mechanical principles, and positions the mounting thread around 1” inside the tube that is the next larger on the scope. At the flange ring against the tube end, there is a shoulder making a tight fit inside the larger tube, giving the joint two separated mounting points – and so there is less likelihood of a wobble developing at the joint.

History

DSC05595 closeRegrettably no info is available. The scope was bought from a dealer in Littlehampton, West Sussex, in August 2017 – an Ebay Buy-it-Now item that was suddenly withdrawn, so I chased it. Presumably there was a failed sale, or other interest.

Accession number 313.

Watkins & Hill “Customs” scope

This telescope has all the features that you would seek for in a vintage instrument. Apart from that it is a classic design of three draw, mahogany barrel telescope, medium sized at 23” long extended, and complete with leather case – and it works well.

The first major good feature is that the maker is engraved on the first draw as Watkins & Hill, located at 5 Charing Cross, London – with the engraving being “Crofs”, in the old style of script. This Francis Watkins was the grandson of the Francis Watkins who partnered with John Dollond in taking out the original patent on the achromatic doublet, and indeed his Grandfather had run his business from these same premises, at 5 Charing Cross. In partnership with William Hill they operated from 1822 until 1856, when the business was taken over by the Elliott Brothers.

There is another engraving on the first draw, and also on the brass sleeve at the end of the wooden barrel, which is “CUSTOMS 1827”. Not only does this tell us that the telescope was made in 1827, it does indicate that it was bought by the Customs authorities for issue to their officials, presumably for use in ports or lookout towers. So just this engraving confirms the date and the first use made of the telescope.

Smaller features

The telescope has some further interesting features, first all the screws into the wooden barrel are the original screws, very neat and flush with the brass sleeves. Second the first draw has a mark around the brass to indicate the focal point for distance viewing, to assist the different users. Finally, as an antique it is good that all the screw threads run freely, so the lenses are easy to clean. The exception to this is that one of the lenses in the second cartridge, at the end of the first draw, seems to be cross threaded, and is not going to move. A possible reason for this is that while all the draws are labelled with an assembly ID of “II”, this cartridge is labelled “VI”, so possibly this has been accidentally swapped from another telescope, during a Customs cleaning session. Nevertheless the assembly works fine.

When closed the scope is 7.5” long, and it is 1.5” OD. The slider that would close the eyepiece has been removed. The mahogany of the wooden barrel is still well polished, and has a lovely colour.

Recent history

Bought on Ebay in 2017, this scope was offered earlier on Ebay but the buyer failed to pay up. On the second round I managed to win the scope – at over 20% more than the previous winning bid! It came from the estate of an antiques dealer in Nairn, Scotland, and he had owned it for at least 30 years. So possibly the scope was used by the Customs in Scotland somewhere!

Watkins & Hill

This firm was a well established supplier of good quality telescopes, and worked “By Appointment to” the Dukes of York and Clarence in the early 1800s. They were also suppliers to the East India Company and to London University. At some time they  worked in co-operation with Negretti & Zambra, according to Gloria Clifton.

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Telescope with the possibly original case

Accession number 314, bought October 2017.