21/03/2014 12:27 GMT | Updated 20/05/2014 06:59 BST

Getting Saucy at the Museum of London

"I tried to read it to myself in the mirror this morning but I couldn't quite get the words out," whispers Linda, a volunteer tour guide at the Museum of London's Archeological Archive and Research Centre. She fusses with the collar of her blouse and passes us a sheet of paper, on which is written I Have A Noble Cock. It's a fifteenth century poem written by an anonymous author, which she suggests we read to ourselves.

It's Friday afternoon and I'm in the museum's entrance hall, about to begin a "Shoreditch's Saucy Side" archeological tour. I'm joined by seven others hoping for a fun and humorous exploration of erotica. But with Linda and her fellow tour guide, Jeanette, unable to utter any "naughty" words, we're not off to a promising start.

We finish the poem with a collective titter and follow our blushing guides into the main room of the archive, a bright, cold space filled with endless rows of shelving units. Each holds a stack of cardboard boxes labeled with printed sheets detailing their contents - one simply reads "teeth".

We arrive at a table bearing a small white ceramic object carefully housed in a foam box. The delicately patterned piece, 105 mm long, is remarkably intact, despite dating back to the seventeenth century. An elderly woman in the tour group leans on her walking stick and peers at it uncertainly.

"I don't see anything rude about that," she says with disappointment, mirroring my own sentiments.

But how wrong we are. Shuffling her laminated information sheets, Jeanette mumbles that this funnel-like object from Holland could, in fact, have been a ceramic dildo. Ceramic! My enjoyment of the tour instantly increases ten-fold.

The next item appears to be an oversized brown coffee bean. Wrong again. It's a copper badge shaped like a vulva, with a wobbly French inscription that reads "con por amors". Linda is unsurprisingly reluctant to tell us this means "c*nt for love" in English.

In the seventeenth century prostitutes would have worn such badges to advertise their wares and make them known to punters. I stare at in fascination, wondering what sights it must have seen over its long life.

According to Linda, the wearing of replica male and female reproductive organs dates back to Roman times, when being in possession of such items was considered good luck.

"I went to Pompeii last year - there were penises everywhere," nods a man at the back of the group, his leather jacket crinkling as he leans towards the next item. It's an eighteenth century wind chime made of animal bones whittled into tiny penises that, Jeanette whispers, would have been given to a young girl by her father as a mark of protection. I can practically feel Freud turning in his grave.

The next hour passes quickly as we move from table to table, examining more penis and vulva shaped items. Some are in sealed plastic boxes and others are "handling objects"; we all get to fondle a seventeenth century phallic cup and a nineteenth century penis-shaped pepper pot.

But two American women dressed in fur coats and heels are visibly unimpressed. They've wandered over to another table and are peering in confusion at a display of cracked white tiles decorated with figures painted in blue.

Jeanette tells us the tiles were found in 1962, when a fire ripped through a pub in Fleet Street and exposed a hidden room boarded up at the back. Linda chips in by musing that the sexual depictions on the tiles could indicate the room was used as a brothel or as a secret space for masturbation parties.

We all lean in to examine the tiles, made of Plaster of Paris and dating back to the eighteenth century. One depicts someone getting spanked while one has a woman in a basket being lowered onto a man, which is apparently how a King would have his women delivered to him in the Palace of Versailles.

It takes me a few minutes to work out the scene in the middle tile, which is by far the most obscene thing I've seen today. "These are very naughty people," Linda tells us wisely. "I'd rather you came to your own assumptions about what they're doing."

And for once I'm in agreement with Linda. I couldn't possibly write in words what those naughty people were up to; you'd have to go and see for yourself.