'It was an exciting time. We all realised the importance of this great medical and social experiment'

"It was a time of excitement and enthusiasm from a personal level," he said. "We'd just done five years at medical school. We were dying to get into our chosen profession and start work.

"But also, it was an exciting and enthusiastic time generally because we all realised what the importance of this great medical and social experiment.

"But most of us in my year group were enthusiastically approving of the National Health Service. It was a generally exciting time."

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During his first year, Dr Boyd was paid £200. However, since all junior doctors at that time lived together in a residency at the hospital - a practice phased out from the 1970s - half his salary was automatically deducted to pay for laundry, meals and lodgings.

Dr Boyd during National Service in Nigeria

Nonetheless, Dr Boyd, now 91, said he "very much regrets" the loss of this practice. He said: "It was a great thing. Camaraderie is the word. We stayed there and we all met for meals, we all were in the common room in the evening, and we learned from each other.

"Weekends usually started at lunchtime on the Saturday. We didn't think about 'contractual hours' - I don't remember ever signing a contract. We just did what needed to be done."

Speaking at his home in Morningside, Edinburgh, the retired physician said the NHS he joined in 1949 was a very different place to the NHS of 2018.

"The spectrum of disease then was entirely different to what it is now," he said. "When I was a student, tuberculosis was rife and for example if a child came in with a diagnosis of meningitis-tuberculosis, it was a death sentence.

"Then at the beginning of being a house officer, streptomycin came in - and it was a miracle. They survived."

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Dr Boyd said the levels of poverty he encountered as a young medic in Edinburgh are also long gone. As a student, he spent a period assisting at home births in the Leith area with midwives.

"That was an occasion where I was first confronted with real poverty. Some of the worst slums in Scotland were in Leith. Often there would be nowhere to put the baby except in an empty drawer, and sometimes there wasn't very much food.

"I remember one occasion where the delivery was quite prolonged. The men vanished, of course - off to the pub or wherever - and it was either a neighbour or a female relative who was around. They'd be offered a cup of tea and that was it.

"Anyway, it was going on and on and the student midwife said 'I'm getting really hungry'. So we pooled our resources - the midwife and myself - and I went out and got fish suppers.

"And we all - the poor mother-to-be, the attendants, myself - we all ate fish suppers. It was probably the best meal she had had in a long time.

"I didn't come from a posh family, but I'd never encountered poverty like that.

"I shared with a very good friend of mine, another medical student, and when we came back from these places the drill was that we went straight back to our bedroom, put a newspaper down, stripped and started to look for the 'wildlife'. There was everything: fleas, lice, bedbugs. That's something not seen nowadays."

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However, Dr Boyd laments the rise of a "culture of blame" in the NHS over the decades.

He said: "There were difficulties then when I was younger, but there is a difference in attitude. Things went wrong in those days as well, of course, but they didn't have the climate of blame and fear of doing something wrong and being blamed and sued for it. That didn't exist.

"Another disease you don't see now is polio myelitis. Now I can remember as a house physician admitting a young male psychiatrist from the local psychiatric hospital at Larbert, with acute polio myelitis. He progressed very rapidly to the extent that his respiratory muscles were affected.

"Now in the 1930s Lord Nuffield - the 'Morris' of the Morris cars, and at that time a millionaire - he had gone round the hospitals in the UK presenting what was known as an 'iron lung'. These were the old negative pressure respirators. It was like getting into a coffin - you were enclosed in there with a seal round the neck, and just your head exposed.

"Well, Falkirk Royal had an iron lung. I had never had training in using it and I don't think any of the other staff had either. It was just there, ready for use, but it never had been used.

"I remember that being a very traumatic experience, and the poor chap died afterwards. I had never seen a team of nurses cry before but we were all very distressed. That's one of the bad things I remember.

"But nobody said 'why did this man die?'. The attitude was from relatives 'thank you doctor for doing all you did'. It was different."

Following his National Service in Nigeria, Dr Boyd worked at various hospitals including the Eastern General Hospital in Edinburgh, where he was based in the department of respiratory disease alongside Sir John Crofton, the famous pioneer of the 'Edinburgh Method' which helped eradicate tuberculosis.

"He was a fantastic man," said Dr Boyd. "He was not only a brilliant physician and researcher, but he was a very humane man."

Later, seeking a consultant post, Dr Boyd became the first ever consultant physician employed by the NHS in Caithness and Sutherland when he took up a post at Caithness Central Hospital in 1964.

He was tasked with setting up the region's first acute medical unit, which served a population of around 35,000-40,000 people. Besides Dr Boyd and his senior house officer, the staff consisted of one consultant surgeon, a consultant obstetrician, an anaesthetist and a GP.

Dr Boyd said: "It was fine, but I found the isolation as a consultant hospital doctor something which worried me. I'd always been in the situation where if there was problems you always had somebody to spark off - but there was nobody.

"I began to think 'I'm going to develop a God Almighty syndrome here', that everything I say is correct. I missed that contact, so I came back to Edinburgh in 1970."

The remainder of his career, until he retired from clinical work in 1988, was spent in the capital.

More recently, he has experienced the NHS as a patient - having coronary stents and a pacemaker fitted - but also through his granddaughter, who is a GP.

"Her stories of pressure on beds - I don't remember that quite so much," said Dr Boyd. "We were certainly busy and we worked long hours, but we enjoyed them. We didn't have the problem of the elderly so much though. Being 75 back then - you were really old. Being 91, as I am, that was unheard of."