Background
Glossop Brook is a tributary of the River Etherow. It is formed near Shirebrook, where Shelf Brook meets Hurst Brook. Shelf Brook passes through Old Glossop and Manor Park on the way to Glossop Brook, while Hurst Brook flows down past the golf course and through Shirebrook estate before meeting Shelf Brook.
From there, Glossop Brook passes west through Milltown, Howard Town (Glossop itself) and Dinting, with Long Clough Brook joining it to the north of Simmondley, before it meets the river Etherow at Brookfield. The river Etherow then runs south to join the River Goyt at Marple Bridge.
Glossop Brook has a history of flooding, with notable occasions being in 1930, 1946, 1969, and most recently in 2002. Although flood defences have been build over the years, reducing the likelihood of floods, the river is still prone to flash flooding, as rain in the hills around flows down the various brooks and streams into Glossop.
The cache
You are looking for a small 7ml tube, hidden near the river. You'll need to bring your own pen, as there isn't one in the cache, and you do need to sign the log to claim the find.
