May 17 presents a further opportunity for collectors to purchase unique photographs of Captain Scott's tragic expedition to the south pole.

In a Bonhams London auction on March 30 that coincided with the 100th anniversary of Scott's death, several images taken by Herbert Ponting of the initial stages of the expedition sold well, including a shot of the Terra Nova, the expedition's ship, which made £13,750.

Captain Scott writes in his diary

Now three further photographs taken by Ponting of the expedition arrive at Bonhams.

A striking photograph of Scott writing in his diary on October 7, 1911 has an estimate of £2,000-3,000.

Ponting's photographs document 14 months at Cape Evans, between 1911 and 1912, where the expedition prepared for the march on the pole.

He left the expedition in February 1912 along with eight others, as the rest of the party headed south.

Captain Scott was among a team of five that made it to the south pole, five weeks after Norwegian rival Amundsen. Scott's party failed to return to safety.

A photo of the Terra Nova at Cape Evans, and a shot of a grotto in an iceberg with the Terra Nova in the background will both carry £3,000-5,000 valuations.

We are confident that the poignant photographs could surpass the top end of their estimates, considering the success of the previous sale, which captured the imagination of buyers.

The March 30 auction also featured a letter written by Captain Scott just days before he died, which sold for £163,250, beating its estimate by 8.8%.

The auction will also feature David Bailey's 1965 photograph of the Kray Brothers, which is valued at £5,000-7,000, and a photograph of Charles Dickens' wife, estimated at £6,000-8,000.

We're delighted to offer a signed letter from explorer Ernest Shackleton, written to his wife less than a year before his death.