This is the infamous 'kissing shuttle' that caused so many early deaths amongst weavers. The easiest way that the thread could be installed in the eye was to 'kiss' the shuttle and breathe in sharply. This carried minute specks of cotton into the lungs and could cause Byssinosis, a disease of the lungs that could restrict breathing and in some cases cause death.
A secondary problem was relayed to me by weavers in the LTP. It was that many old male weavers chewed tobacco in the shed and in consequence there was a build up of tar-like substance round the eye. If one of these weavers was teaching a young weaver they had to ignore feelings of disgust and kiss the shuttle.
Thankfully in the first half of the 20th century they were banned but it took a long time for them all to be replaced. In some cases into the 1950s.