From the Black and White Budget of 2/00, IL offers for your amazement a few pics of such a device! As a former Infantryman (many, many years ago) your contributor notes the "attractions" of such a device. When deployed as illustrated, the "Sharpshooter" Modern Shield offers a perfect aiming mark for an opponent, it has a tiny firing aperture with no provision for oblique firing from prone, it could only be used on flat ground, it weighs a mere thirteen pounds - what could possibly go wrong! Needless to say, the "Sharpshooter" shield never saw action in South Africa.
In fairness, the inventor of this unblushingly useless device claims to have hardened his "Sharpshooter" shield to withstand rifle bullets at 400 yards and "light" machine gun fire at 700 yards. An interesting distinction, as both fire the same cartridge in essence. Added to his marching burden, our average overloaded Tommy would very soon discard such a device.
Admittedly, body armour was tried during the US Civil War and found to be useful for static defensive positions - machine gunners - in WW1. Body Armour was widely used in the American War in Indo-China - however, those examples are a technological leap ahead of February, 1900.
Regards to all