What is a messenger?
The work horse of water sampling is the simple messenger, the bullet-shaped weight which strikes the trip mechanism and snaps the sampler shut. Send the messenger down the line when you are ready to take your sample – you choose where and when. When you lower your bottle or dredge into the water,it remains open until you close it.
Messengers afford nearly foolproof operation – highly reliable and problem-free. As with other essential equipment, your sampler is only as good as the messenger on hand. To prevent lost opportunities, carry several spares.
Most Wildco samplers work best with an 11 ounce messenger. Some water samplers need special messengers. Lighter ones are good for longer air drops. The weight of a messenger defines the distance it must fall before striking the water. A too-heavy messenger with a too-long air drop may damage your sampler. For both 8 oz and 11 oz messengers, maximum air drop is 50’ (15 m).
Teflon®-coated solid messengers are good for trace metal sampling or for very acid environments. For sampling in series, each vertical bottle uses a messenger to signal the closing of the next bottle.
A split messenger can be placed anywhere on your line, not just at the end. It literally comes on and off with one hand. The split messenger includes a spring to hold the barrel closed and a hole for attaching a lanyard.
A 45-B40 shock absorber may be needed to protect the trip mechanism on the sampler if the messenger has a long drop through the air and/or a short drop through the water.
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