The truth of the matter is that a person can make a lot of money from work that most people refuse to do because they think it’s beneath them, dirty and unpleasant. So when someone says “where there’s muck there’s brass” you can be certain that he or she is talking about the upside of a job to which others only see downsides. The saying is sometimes known as “where there’s muck there’s money.”
John Ray published his book “A Collection of English Proverbs” in 1678 and included this similar proverb among the proverbs:
Muck and money go together.
That being said, the Dictionary of European Proverbs by Emmanuel Strauss identifies the date for this English proverb “Where there’s muck there’s money” to 1476.
The word muck dates back to the 13th century and is from the Germanic muk — also written as meuk — meaning “soft” which comes from the Old Norse words myki and mykr, meaning “cow dung.” These trace back to the Latin word mūcus meaning … well you know what that means.
So it is a well-established fact that muck has referred to the less desirable natural functions of humans and animals for centuries.
The word brass is from the Old English word “bræs” that refers to an alloy of copper and tin (now bronze) and that is an alloy of two parts copper and one part zine in modern times. Although it’s a mystery word with no known cognates beyond English, it seems to be related to the Old Frisian word “bres” meaning copper and the old Middle Low German word “bras” meaning metal.
The word brass came to mean copper coins collectively in 1599 — and money in general in 1601 — and was a popular expression especially in the north of England.
The phrase “where there’s much there’s brass” came into its own around this time and helped spread the popularity of the word “brass” as slang for money. The brass/money association came about because of the association between the colour of gold coins and the value of brass as a scrap metal at the time.
It has remained a recognized slang term for money and in 1984 when the one pound coin was introduced during the Margaret Thatcher administration in the UK, that particular coin became know as the Brass Maggie.
On a completely different note, the Isle of Muck is a picturesque island just off the coast of Scotland that boasts a population of 34 people.
Historically Speaking 