The Watts Director No 5 is an early predecessor to the goniometer such as the Wild G10 in my collection. The instrument was primarily designed for the military to aid in field surveying and artillery aiming. The instrument is an early example of this model (introduced in 1915) and comes with two eyepieces / telescopes allowing different magnifications. The original case is also present, however the strap is broken. The original tripod is missing. Quite interesting is the plumb lead which is stored in a 5 shilling copper paper bag from Barclays bank. The two telescopes can be interchanged bu unscrewing the bayonet, sliding out the telescope end and replacing it with the other.

The instrument has a 50 degree up (elevation) and down (depression) mode. Horizontally it has 360 degrees. Both scales are operated by a micrometer which has a 5 minute direct reading making it a rather coarse instrument. With some experience it can be read to 1-2 minutes on the micrometer scale. What makes it special is the worm and ratchet mechanism on the horizontal circle. This seems to preceed those on my sextants (survey or navigation) and allows both a free movement as well as fine setting. The instrument is equipped with a box compass and levels for both the horizontal circle as well as a separate for the vertical allowing it to be used as a leveling instrument as well. What is special is the additional level on the telescope itself. This level is mounted in a box to the sides of the telescope and can be adjusted. It has a separate scale for 10 degrees elevation / depression which can be directly read to 2 minutes (and estimated to 1 minute). The micrometer only operates the level and I am still figuring out what its function has been as there is a large level on the vertical scale anyway.

The instrument seems to have been sold as 'surplus' after WWI as indicated by the plaque on the case stating "The miscellaneous Disposals Syndicate Ltd". Research shows that this company sold former (WWI) government articles in at least the 1920's. As the director No5 was superseded by the much compacter No7 in the 1930's it was probably sold around that time.

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Nigel Evans