A huge collection of circus-themed US covers has seen some of the highest bids in Robert A Siegel Auctions Galleries' July 23-24 US and CSA Postal History and US Possessions auction in New York.

This example of the 'Southern Menagerie is Coming' cover sold for $3,750 at Siegel in June

The collection is housed in a large album, with more than 60 circus-themed covers, the earliest including four examples franked with 3c 1861, though these are generally faulty.

It was originally expected to sell for between $750 and $1,000, but soared to a 600% increase on estimate, making $7,000.

Also included are many covers bearing stamps from the Bank Note issues, nearly all of them elaborately illustrated. The most interesting groups are those relating to Buffalo Bill and PT Barnum, a legendary showman and founder of the famous Ringling Bros. and Barnum & Bailey Circus.

The highlight of the collection was an unused "Southern Menagerie is Coming" civil war patriotic design, which shows a caricature of Confederate soldiers as circus animals.

A used example of the cover, bearing a 1861 3c Rose, sold for $3,750 at Siegel in June.

However, the top lot of the sale was a fantastic collection of postal history relating to the Mexican-American war (1846-1848), which sold for $17,000 - a 13.3% increase on its pre-sale estimate of $15,000.

The complete history of the Mexican-American war is charted over the course of the collection, complemented by an extensive write-up and transcription.

Included are pre-war letters from military forts in Louisiana, important letters from US officers describing troop movements, and many extremely scarce postal markings.

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