Need information on adjusting tool

I believe this tool is used for adjusting rear sight on MKI Lee Enfield.
Would anyone know how this tool is used.

Makers name W J Jeffery&Co Gun & Rifle makers King St St James London

Actually I came across one of those the other day. I'd be interested to hear from the experts as well.

Similar tools have been used on the M1903 sight as well. I call them ventometers, though strictly this applies only to the ones that push the windage bar laterally. The device is clamped onto the leaf with the slide pushed well onto the moving part of the tool and the vernier is used to move [push or pull] the slide up or down a measured number of minutes. In some cases the milled head has graduations on it as well. Some experience is needed to get consistent results with these devices.
I doubt if Jeffrey actually made them. Most seem to have been made by AG Parker.

This Ventometer has the ability to either Pull or Push the slide. It will not fit the rear sight of a Charger Loading Lee Enfield ( CLLE ) https://www.milsurps.com/images/impo.../10/LS12-1.jpg

https://www.milsurps.com/images/impo...9/10/LS6-1.jpg

I've just learned from posts over a year old on the Martini Henry site how the Ventometers with the blade running off to the side of the device can be used for lateral adjustments, as Mk VII stated earlier. Wow! I wondered what that feature was for. Duh...Man, you guys are full of a wealth of knowledge about such things! Thank you!! :thup: