Russell Johnson and Patrick Abbott toured MacKillop College Bathurst (Dio)

It was like stepping into a time machine for Patrick Abbott and Russell Johnson, who taught at the school between 1972 and 1974.

Back then, it was known as the Diocesan Catholic Girls High School.

The pair both came from Canada and began their teaching careers at Dio, where they were 20-something-year-old men with long hair and foreign accents.

Though a lot has changed since the pair worked at the school, memories came flooding back as soon as they stepped through the doors.

Mr Abbott, who worked as a science teacher during his years at the school, reminisced about several student escapades.

One of these involved a bomb.

"They were always keen on pranks," he said.

These practical jokes began with various prank calls to the school, warning of a possible bomb.

The calls would come in so regularly that staff at Dio wrote them off as nothing but empty threats.

That was until one day when the threats became a reality.

"There was a big boom, and a whole bunch of smoke in the girls' toilet," Mr Abbott said.

A police investigation ensued and the science department also made it their mission to get to the bottom of the broken bathroom.

The evidence involved three girls with blackened faces, black smoke everywhere, a broken toilet and two doors that were pulled inwards off the hinges.

"So the three young girls involved were being interrogated and finally they cracked. Initially, they said 'oh, we have no idea what happened, we just went in to the toilet and it exploded'," Mr Abbott said.

"But what had happened ... they had gotten some calcium carbide from a boyfriend in a public school ... but when calcium carbide hits water ... it's an exothermic reaction and it will self-ignite.

"And it self-ignited while they were lighting a match, which only augmented the explosion and blackened their faces and they were so terrified that when they were trying to get out they ripped the door off its hinges."

Mr Johnson's most fond memory is from 1973, when the Duke of Edinburgh travelled to Australia and made a very important stop in Bathurst.

Mr Johnson worked in the physical education department and was tasked with teaching students "something semi-remarkable" to present to Prince Philip to impress him.

"I thought we would do some sort of gymnastics thing," he said.

"So we had a big pyramid of people standing on their hands at the end. After we finished it, he [Prince Philip] came up to me and said 'did you teach those girls that?'."

Meeting royalty was certainly something that went down as a career highlight for Mr Johnson.

But the biggest highlight was that of developing a rapport with his students, all while learning the ropes of teaching.

"When I first came, it was a really steep learning curve for me because I discovered that some girls didn't like PE, and some girls didn't want to come to PE," he said.

"So I had to rethink the way I had to teach. I found it a challenge, but I managed."

And even 50 years on, he was inundated with these memories while taking a tour of the updated school grounds.

"It feels the same and different for me. Once I see girls or students walking in the corridor, I just sort of change and want to converse with them," Mr Johnson said.

For Mr Abbott, the nostalgic journey of his time at the school culminated during his September visit, but began when he discovered the school's online vault.

This vault contains hundreds of photos and videos from decades gone by, can be accessed by any current or former staff or students and was set up by Robert Newton.

"I mean, it's just fabulous to be able to do this [return to the school], and ordinarily it wouldn't be as interesting, except for the archive," Mr Abbott said.

"When I was able to start going through the archive, and seeing everything there, it just brought back a flood of memories, and essentially you're able to almost relive the experience, which I think is extremely rare."

After a long and varied career between teaching and finance, Mr Abbott has now retired and resides in Hawaii, where he grows pineapples.

Mr Johnson spent the remainder of his career teaching at Marist College in Canberra and has since retired.

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