Sporting a curled moustache and flowing velvet tie, the photograph captured of a handsome young Charles Rennie Mackintosh - aged about 25 - by distinguished Glasgow photographer James Craig Annan in 1893 is the picture we all know of Mackintosh today.

And while other photographs exist of Scotland's most celebrated architect and designer of the 20th century - including Emil Otto Hoppé’s portraits of Mackintosh as an old man in 1920, none have been uncovered showing Mackintosh as a young boy. 

That, however, may not be the case any longer, thanks to the discovery of a photograph from a Glasgow school which was taken while Mackintosh was a pupil there. 

Mackintosh attended the former Allan Glen's School, a private institution for the “sons of tradesmen or persons in the industrial classes in Glasgow” from 1880, when he was 12, until either 1883, when he left to begin his training as an architect at Anderson College. 

Recently, Allan Glen's Membership Secretary Mike McCreery came into possession of the oldest known school photograph, dated as having been taken in 1880, which had notes attached to it which suggest that a young Charles Rennie Mackintosh was present in the photograph. 

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After reading about how a research team at the University of Dundee’s Centre for Anatomy and Human Identification (CAHID) created the "most lifelike" reconstruction of the face of Bonnie Prince Charlie using death masks of the prince, a committee, headed by John McGee, treasurer and historian of Allan Glen's, commissioned Dr Tobias Houlton at CAHID to conduct a facial recognition comparison study to try and identify a young Charles Rennie Mackintosh within the school photo.

Mr McGee said that Mackintosh is considered one of two boys who went to Allan Glen’s “who are right up there as our top alumni” along with English actor and novelist Sir Dirk Bogarde.

He told The Herald: “We know from books and also from newsletters and magazines from the early period of Allan Glen’s that Charles Rennie Mackintosh did go there. Although his actual admission record to the school doesn’t exist, it is well documented that he went to the school. He was born in 1868 and brought up in Townhead, which is about five minutes from where Allan Glen’s was. He would have gone to Allan Glen’s when he was 12 in 1880, the year the photograph was taken, and stayed for three years as far as we know, which wasn’t unusual in those days.”

He believes the only reason that the photograph exists is because Charles Rennie Mackintosh was in it.

He added: “The photo would have come from an ex Allan Glen’s pupil. We can’t remember exactly who it was that gave us it. They somehow obtained this photograph. As far as we know it’s the only photograph that’s still extant from Allan Glen’s from the Victorian era. 

The Herald: Allan Glen's School class photo from 1880.Allan Glen's School class photo from 1880. (Image: John McGee)

“You’ve got to come in to the 20th century before you find any other photographs of Allan Glen’s. Why that one photograph existed is because we believe that Charles Rennie Mackintosh was in it. That’s why we commissioned the research.”

Tasked with estimating the probability of one of the schoolboys being the young Mackintosh, Dr Houlton, a specialist consultant in Craniofacial Identification and Forensic Imaging, compared the photo against a collection of known photos of the architect and designer in his adulthood. 

Dr Houlton told The Herald: “It was a fascinating project and quiet an exercise given the number of schoolboys featuring in that picture. John McGee got in contact and mentioned that there was an old photograph of the class dating back to 1880 from Allan Glen’s School and that Charles Rennie Mackintosh was a student there at the time, and the prospect of him potentially being one of the boys in the photo.

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“The quality of the photograph was pretty good given how long it’s been in existence. It hadn’t deteriorated too much. Obviously a big concern with the facial comparison is of course that there’s such a dramatic time difference between the recognised adult image of Charles Rennie Mackintosh and then the prospect of him being a 12-year-old prepubescent boy. Particularly with males, with the introduction of testosterone, faces can change quite considerably.”

Informed by the facial traits identified when analysing the known images of Mackintosh as an adult, Dr Houlton performed an initial facial review to refine the search and eliminate pupils that did not demonstrate a “holistic conformity” to Mackintosh.

Six pupils - from an initial 55 - were selected for further analysis using the morphological technique of facial image comparison. Dr Houlton then rated the remaining six in terms of their facial similarities and differences to Charles Rennie Mackintosh. 

The Herald: The six pupils selected for focussed facial image analysisThe six pupils selected for focussed facial image analysis (Image: Dr TMR Houlton/University of Dundee)

In his detailed analysis, Dr Houlton effectively ruled out Pupils 1, 3, 4, 5 and 6. However, he rated Pupil 2 as follows: “A holistic similarity in face shape and composition exists. There is also a similar consistency in hair density, texture, and style. 

“The more pronounced forehead, jawline, nose shape, eyebrows and facial creases in CRM has the potential to occur in Pupil 2 following puberty.”

While the analysis indicates that Mackintosh is “potentially Pupil 2”, Dr Houlton in his report, notes that such a conclusion needs to be viewed “with considerable caution”.

The study notes: “Due to rapid developmental changes that occur during childhood, especially throughout puberty, the morphological characteristics of facial features lack stability and limit the strength in conclusions that can be made when comparing Charles Rennie Mackintosh and the pupils of Allan Glen’s School. Due to rapid developmental changes that occur during childhood”.

The Herald: Charles Rennie Mackintosh face transitionCharles Rennie Mackintosh face transition (Image: Newsquest Design)

Added to that were limitations which “exist in terms of image quality” and “the fact that the morphology of pupil faces could only be assessed from a single perspective”, as well as the chance that Mackintosh “was not necessarily present on the day the photograph was taken”. 

Speaking about Pupil 2, Dr Houlton said: “There were qualities in one boy’s face that I picked out in particular that kind of offered leanings that if it was to be anyone, if he’s present in that picture at all, there’s consistencies in the face, air texture and style that leans to that particular boy.

“There was a holistic similarity between them. Things were generally consistent in terms of the placement of features, albeit that once he has puberty there will be potentially fairly drastic changes that occur to the face, the sort of masculinisation that will experience where the brow becomes more pronounced, the jawline becomes more squared and the chin might become more pronounced. There’s these deviations that will invariably occur with age and puberty that we’d have to bear in mind. 

“I still sense with pupil 2 that even with the influence of puberty there’s still certainly consistency in the hair density and texture and the style that he had his hair in. These are things that will invariably change with time to some extent. 

The Herald: Portrait of Mackintosh as an old man by Emil Otto Hoppé (left) compared against an image of Pupil 2 (right)Portrait of Mackintosh as an old man by Emil Otto Hoppé (left) compared against an image of Pupil 2 (right) (Image: Creative Commons/GSA Archives/John McGee)

“In his youth as a young adult male Mackintosh certainly had very thick, healthy, luscious hair and that distinct curl as well which you can see in the young boy. I think the more pronounced forehead, the jawline and the fact that Pupil 2 had quite distinct facial features around the mouth area all kind of fall in line with what we could see with Charles Rennie Mackintosh.”

Despite the analysis not conclusively identifying a young Mackintosh in the photo, Mr McGee expressed his satisfaction with the outcome. 

He said: “We knew it might not be 100% conclusive but we’ve had a committee meeting and we are satisfied that to whittle it down to one probable boy is a pretty good result. The committee felt that was as reasonable a result that we are going to get.”

Meanwhile, Dr Houlton called on the public to make up their own minds. 

He said: “I would certainly invite people to look at the school photograph and see for themselves what they feel. Often people have an instinct and sometimes that instinct is correct.”