Thirteen-year-old Richard Beale’s lack of attention to his mathematics studies more than 200 years ago has been exposed by the Museum of English Rural Life (MERL), which has pointed out the teenager’s doodles – including an image of a chicken wearing trousers – on pages of equations written out in 1784.

The museum, which acquired a set of 41 diaries belonging to the Beale family in 2016 and added Beale’s maths book to the collection last month, caused a viral sensation when it tweeted images from the teenager’s book over the weekend. The boy, from a farm in Biddenden, Kent, used the book for writing out mathematical problems. The museum’s programme manager Adam Koszary said Beale had a beautiful hand and that his equations “laid out like a dream”.

“But, like every teenager, mathematics couldn’t fill the void of Richard’s heart. Richard doodled,” Koszary wrote on Twitter, sharing Beale’s drawings of “beautiful ships, lighthouses, street scenes and trees” and the family dog, who “pops up all over the place” in between the maths.

The Museum of English Rural Life (@TheMERL) We think his family owned this dog, which pops up all over the place. pic.twitter.com/nSHydhpK5o

“But there’s one thing we didn’t expect to see. Richard put an 18th-century chicken in some trousers,” Koszary added, sharing an image of the mysterious fowl, which captured the imaginations of what the museum said were tens of thousands of readers.

One fan was Harry Potter author JK Rowling, who called the doodles “truly wonderful”, and promised Koszary, who had requested she make her next series of novels “the adventures of a chicken who wears trousers”, that she was “way ahead” of him. “He’s best friends with a duck in a balaclava,” she wrote.

Koszary said that “archives are full of this kind of stuff”, and that he hoped the popularity of his tweets would “get people to come and use them”. “When you see a 13-year-old from the 18th century doing the kind of doodles that kids are doing today, it is so relatable – there’s an instant connection,” he said. “Also, there’s the fact it’s just so stupid.”

Guy Baxter, associate director of archive services at the museum, said that conspiracy theories had already sprung up about the chicken after the story went viral. “Is it really a chicken? Is it really wearing trousers? Why do the trousers appear to be solid like Wallace’s in The Wrong Trousers? … Was Richard Beale acquainted with the town of Hensbroek in the Netherlands? Or was he into heraldry?” said Baxter.

Facebook Twitter Pinterest Doodles from the pages of Richard Beale’s maths book. Photograph: Museum of English Rural Life

While he admitted that “the link with Wallace and Gromit is unproven”, he explained the link to Hensbroek: the Dutch town’s arms “are a famous example of canting, which uses a pun on a name to inspire the design”. Hensbroek’s literal meaning is “hen’s pants”, and “an enterprising [15th-century] mayor used this to create the canting arms” of a hen, wearing pants “and put the town on the map”, said Baxter.

It is unlikely that Beale had been to the Netherlands, “especially with the fourth Anglo-Dutch war being on at the same time,” said Baxter. “But it is possible that he knew about canting arms. Or maybe he just had a vivid imagination.”

Dr Ollie Douglas, curator of the MERL object collections, said that Beale’s drawings “resonate powerfully with us now because it is through these same personalised interactions that we create and shape the stories of our own lives in the present”.

“And for those of you fearful that the digital age has put an end to the kinds of marginalia and informal records of our lives so brilliantly revealed in this 18th-century maths book, fear not. Social media is awash with highly personalised engagements and commentaries on the world,” said Douglas. “You only need look through the responses to this single Twitter thread (and that fact that a readymade chicken-in-trousers gif was available for us to shamelessly retweet) to see that the messy complexity of our world is still being shared and that we are all still doodlers at heart.”