Tom Thomson's Spring Sunset, Algonquin Park Spring 1916

I used this painting "Spring Sunset, Algonquin Park Spring 1916" (above and right side in the following graphic)  to justify the Creative Scene Investigation interpretation of  Tom Thomson's "Sunset Spring 1916" (left side in the following graphic). My conclusion was that "Sunset Spring" was painted looking eastward at sunset using the Belt of Venus to augment the sunset colours. The shadow of the Earth and atmosphere contributed to the diagnosis. In sharp contrast "Spring Sunset" was observed painting into the blazing sunlight beams straight from the sun - even though Tom did not include nor could he see the sun below the horizon. 

The two words comprising the titles of both paintings are simply switched "dyslexically". Lawren Harris and J.E.H. MacDonald were running out of fresh ideas in the spring of 1918 as they shifted through the tall stack of unsigned Tom Thomson panels in the Studio Building. Either that or Tom just painted too many sunsets.

Spring Sunset, Algonquin Park Spring 1916
Oil on composite wood-pulp board 8 9/16 x 10 9/16 in.
 (21.7 x 26.9 cm)
Tom's Paint Box Size

The Creative Scene Investigation initially focuses on the lighting and the colours. It suffices to conclude that Tom was looking toward the west after the sun had slipped below the western horizon. 

The orb of the sun was below the horizon to the west

The purplish hue of the cirrus requires special attention. As mentioned it could simply be the scattering of blue light by the ice crystals. Large ice crystals scatter by the Mie principle which distributes all wavelengths mainly in a forward direction. But the short wavelength purple light was more likely scattered by small ice crystals thus invoking Rayleigh...  

In fact, the purple was probably the result of Rayleigh scattering from very fine volcanic aerosols that reach the stratosphere. These molecular-sized particles are excellent Rayleigh scatterers sending short wavelength light efficiently in all directions. Recall that Lassen Peak in northern California exploded in a powerful eruption on  May 22nd, 1915 - less than a year before Tom was painting this sunset. Scattered blue light when mixed with the red of the sunset produces the purple hues observed. It might even have been the purple hues in the upper atmosphere that drew Tom's interest to record what he saw! 

The Creative Scene Investigation next focused on placing Tom's location within the weather pattern of the day. 

The cloud and instability place Tom under the cyclonic companion of the warm conveyor belt. The thick and extensive comma head cloud was likely further north. Tom was actually looking into the dry slot of the comma pattern. Notice the breaks in the mid-level cloud deck further to the west. The winds displayed a southerly component that suggested that the warm front was nearby or to his north. The cold front was not far to the west.

In the early days of satellites (early 1980s), meteorologists were viewing comma cloud patterns for the first time from space. Those cloud patterns revealed the system relative winds and in turn deformation zones. They were the same patterns I saw when I was paddling my canoe. 

I thrived meteorologically using Satellite Meteorology to better understand the weather patterns of the day. Those concepts led to the Conveyor Belt Conceptual Model and my tenure with COMET teaching meteorology and creating online training modules for international students. 

The terminology is still valid and I use it here to illustrate how we might better locate Tom's painting location in terms of the weather. It is likely that Tom was viewing the dry slot in the comma pattern to the west. I have placed the Gold Star locating Tom within the comma cloud pattern in the upper left of the following graphic. These are historical graphics constructed in support of my efforts to help fellow meteorologists within Environment Canada Weather Centres and with COMET. I sketched similar concepts countless times to coworkers at the various weather centres where I studied the weather. 

The weather clues also place Tom fairly accurately within the Conveyor Belt Conceptual Model.

Top-down view placing Tom's likely location within the
Conveyor Belt Conceptual Model looking toward the dry
slot of the Comma Cloud Pattern

Both plein-air paintings were completed at about the same time in the spring of 1916. Tom was using the same Paint Box and his regular assortment of oils on his palette. I even suggest that Tom painted westward looking straight into the blinding light of the setting sun to paint "Spring Sunset" (this painting) immediately after recording "Sunset Spring 1916". I propose that Tom painted looking east and away from the sun first in order to save his eyes from the blinding sun that was perhaps still just above the horizon when he started. Tom was waiting for the sun to lower further. The shock to his eyes would be less when the sun had sunk further below the horizon. 

The views are very different but they could have been painted literally back to back. In "Spring Sunset", the direct beam of sunlight was so intense that the backlit clouds were not optically thick enough to block the energy … the clouds were simply on fire from the bright Mie forward scattering of light.

A lake was to the east of Tom's location in "Sunset Spring" (left in the above graphic). This implies that there could be no lake to his west at that location unless he was on a sharp point of land or an island. This is consistent with no lake being evident in "Spring Sunset " (right in the above graphic) if these paintings were indeed completed at the same location. Tom loved to have lakes in his paintings even more than he enjoyed plein-air art at sunset. Uncharacteristically, Tom did not include a lake in "Spring Sunset ".

My Thomson friend suggested that the location of these views closely match those from a favourite campsite on Whitson Lake which is a widening of the Petawawa River.  The "North Branch Ranger Cabin" once occupied that campsite and a trail also ran through the location. The cabin was still there in the 1940s when they planned to string a telephone line from the Achray Deputy's Headquarters on Grand Lake. The cabin was probably standing in 1916 and would have provided a convenient location for Tom to paint.

The above constraints are satisfied. The bright greens in Tom's painting suggest that it was completed in early summer when the vegetation was lush. Tom would have started his Forest Ranger job and been travelling the area with his coworker Ed Godin from their base at Achray. The details of their trips from the early summer of 1916 are unknown although they did canoe through the area that autumn. 

The view looking westerly from the Whitson Lake campsite is quite convincing in its similarities to the terrain Tom painted looking into the light of the sunset. Those details are included in the next graphic. 

The details of the terrain that Thomson painted are now cloaked by a rejuvenated forest. The similarities presented almost allow us to look over Tom's shoulder as he painted, inspired by the beauty of the weather and nature. Of course, we will never know for certain...

And now a look at the weather pattern that might have been overhead as Tom worked on these paintings. It is consistent that Tom painted looking easterly at location 1 of the mid-latitude synoptic scale weather system. In the time it took for him to complete the first painting, the system had moved northeasterly placing him at location 2 of the Conveyor Belt Conceptual Model. Tom then started to paint looking westerly into the dry slot of the comma pattern. 

It is common for plein air painters to complete a work and then simply turn a few degrees to paint the next. The best way to not overwork a panel is to simply start a new one. Tom certainly did not over-work his art. 

I can spend an entire day within a few square metres surrounded by nature. Several paintings, all different could be created during that plein-air painting session. If the weather is changing, an artist like Tom could easily knock off a half dozen panels in a morning. Tom certainly loved the weather!

Of course, no one can be certain whether these paintings were completed back to back as suggested. The suggestion is based solely on opportunity, probability, topography and science. But I do wish to present the possibility that they were. We will never know for sure but maybe it happened as I suggest. Tom did not have much time to paint in the spring of 1916 - even less than he started his job as a Forest Ranger. It is interesting as well that the names of the paintings are also nearly identical. 

It is very unlikely that Lawren was with Tom when he completed this early summer painting. Lawren would have been at Camp Borden having received his commission on May 5th, 1916. Ed Godin, Tom's coworker was probably with him at Whitson Lake also watching the sunset. We will never know for certain. 

Patron Dr. James MacCallum funded the Thomson Estate Stamp which was designed by MacDonald

      "Spring Sunset, Algonquin Park Spring 1916" as it            
 would have appeared in Tom Thomson's Paint Box       

Inscription recto:

•  l.l., estate stamp Inscription verso: 
• c., estate stamp; 
• u.c., in graphite, TT 70 Thomson Collection @ Art Gallery of Ontario 

Provenance:

• Estate of the artist 
• George Thomson, New Haven, Connecticut and Owen Sound, Ontario, 1935
• Laing Galleries, Toronto 
• Private collection, Toronto 
• Thomson Collection @ Art Gallery of Ontario 

Remarks The board is primed with greyed pale coral (flesh tone) paint.

This painting went into the collection of Tom's oldest brother George

This was indeed a challenging Creative Scene Investigation to complete but the findings are acceptable. Tom was painting looking into the dry slot of a weak and fast-moving early summer weather system from near the North Branch Ranger Cabin on Whitson Lake, a broad section of the Petawawa River. The purple colours high in the sky were due to very fine volcanic aerosols that reached the stratosphere from the volcanic eruption of Lassen Peak the year before. 

To conclude, "Sunset Spring 1916" and this post "Spring Sunset, Algonquin Park Spring 1916" are both important parts of the same story - it would have resulted in one very long Blog. I believe Tom wished to record the differences in the appearance of the sunset depending on which direction one looks. He just did not write that story down or tell anyone about that fact… until now...

Thomson really did accurately paint what he saw. Any deficiency is simply in my ability to convincingly explain what he witnessed. 

Warmest regards and keep your paddle in the water,

Phil Chadwick

PS: Tom Thomson Was A Weatherman - Summary As of Now contains all of the entries to date. 

PSS: Should you wish to have Creative Scene Investigation applied to one of Thomson's works that I have not yet included in this Blog, please let me know. It may already be completed but not yet posted. In any event, I will move your request to the top of the list. If you made it this far, thanks for reading!

Tom Thomson's Sunset Spring 1916

The Creative Scene investigation of this plein air work was a challenge. The question is often asked: "How does one differentiate between a sunrise and a sunset sky?" I rely on the cloud type, their illumination and the wind direction (as revealed by the clouds) for starters. Sometimes the cloud structure can be the solution by placing the painting within the Conveyor Belt Conceptual Model. There are even some astronomical applications but those are typically not available when working with paintings. "Sunset Spring 1916" is an excellent example of the application of these principles. 

This painting was never included in the "Tom Thomson Was A Weatherman" presentations. The clues within the brushstrokes were just too ambiguous. I could not even easily convince myself (and I can be pretty gullible) about the proper diagnosis. I certainly did not wish to mislead or confuse any audience members. Credibility is hard to foster and easily lost.

Including "Sunset Spring 1916" in this blog is certainly OK though. I feel responsible for giving every plein-air painting by Tom Thomson the same fair treatment. Mistakes might be made but I will try to keep them small and forgivable. 

Tom Thomson had made a stop in Huntsville at the home of Winifred Trainor in mid-March 1916. Tom was on his way to Mowat Lodge in Algonquin. He would stay at Canoe Lake until mid-April when he would be visited by Lawren Harris, Lawren's cousin Chester Harris and his patron Dr. James MacCallum. Tom might have painted "Sunset Spring 1916" after his visit with Winnie but before his guests arrived. Tom could have also completed this panel while travelling with his friends. Tom would head to Achray on Grand Lake later in May to work the summer as a Forest Ranger - there was precious little time to paint after that.  

Sunset Spring 1916
 Oil on wood panel 8 1/2 x 10 1/2 in. (21.6 x 26.7 cm) 
Tom Thomson's Paint Box Size 

The colours are somewhat muted in this painting. An examination of the clouds immediately concludes that this must be a front-lit scene. The greens of the spring grasses were relatively bright. The clouds were bright in their central masses and perhaps slightly darker on their edges - consistent with being front-lit. The altocumulus clouds on the distant horizon were darker in keeping with the shadow of the Earth. The Belt of Venus also helps to explain the pink tint of the turbulent cumulus fractus which were the largest clouds in the sky.

But what is the rather bright, circular glow just right of the centre of the painting above the horizon? Is that the sun as suggested by the title?  And in which direction is Tom looking anyway? Might this view even be of a sunrise? There is a problem here...

We could solve this dilemma if we knew the direction of view and whether this was a sunrise or sunset. It would help to know the terrain as well which would reveal the direction of view. I had to go back to first principles looking for a solution. If only Tom had jotted down a clue...

There are four distinct options for this painting:

1. Looking East at  Sunset,  Front-lit, southerly wind, Belt of Venus;
2. Looking West at Sunset,  Back-lit,  northerly wind;
3. Looking West at Sunrise, Front-lit, northerly wind, Belt of Venus; and 
4. Looking East at  Sunrise,  Back-lit,  southerly wind.

The Belt of Venus Explained

The front-lit options explain the colours and the illumination of the clouds best but do not shed any light on the central glow above the horizon. The Belt of Venus even helps to explain the pink tint displayed in the clouds. 

The back-lit options explain the central glow above the horizon but there is a lot of hand-waving and conjecture required to justify that the clouds (which should be optically thick) were bright and not dark in their central masses. The Belt of Venus is not an available option for any back-lit illumination. 

The turbulent cumulus fractus-type cloud is most likely at sunset after a day of heating, instability and wind. Turbulent cumulus clouds are unlikely at sunrise unless the winds are northerly and cold air advection keeps the winds blowing all night as in Option 3 above. 

Cumulus clouds in the morning would need to be associated with a weather system in order to be present. The altocumulus clouds are evidence that this was a possibility. The altocumulus reveals that large-scale dynamic lift was acting in the atmosphere. I could even make an argument that the mid-level cloud had a deformation zone structure to it on the distant horizon. But those patches of cloud could be either coming or going so the deformation zone pattern would be inconclusive anyway.

The water surface was calm which is a common event at sunrise after a night of stabilization and radiational cooling. Calm waters are also possible at sunset if the planetary boundary level had started to develop with the setting of the sun. The calm water is not a definitive clue in this situation.

I considered creating a spreadsheet and assigning points for the attributes that are explained and lesser values for those that require more hand-waving. But that would not be an objective solution either - just a subjective option with numbers assigned. I decided to attempt to diagnose each option one at a time to determine the most likely solution. 

1. Looking East at  Sunset,  Front-lit, southerly wind, Belt of Venus

2. Looking West at Sunset,  Back-lit,  northerly wind

3. Looking West at Sunrise, Front-lit, northerly wind, Belt of Venus

4. Looking East at  Sunrise,  Back-lit,  southerly wind

Option 1 explains the most visual facts in the painting which is not a coincidence (it was always my number one choice). The only stumbling block is the central glow and I can adjust for that weakness by noting Tom's penchant for painting sunsets and some mild hand-waving. It also agrees with the original sunset estimate by whoever named this painting and who obviously knew Tom. Perhaps Lawren Harris was even with Tom at the time!

The bright clouds within that yellow circle cast an aura which might be responsible for that area "glowing". Those front-lit bright clouds were illuminated by the direct beams of the sun that tracked above the level of the low cloud. Those low clouds were left in the relative dark and the pink zone of the Belt of Venus. The mid-clouds were higher and were bathed in yellow-tinted light direct from the sun. 

In addition, the contrast between the bright altocumulus and the overlapping more subdued cumulus fractus, makes them appear even brighter. If you look closely, the sky colour within that yellow circle is not really much brighter than the surrounding sky at the same elevation above the horizon. The apparent bright glow within the yellow circle might be more of an optical illusion and one that artists regularly deliberately employ.

The following graphic may assist further. I applied the second option to Tom's sunset painting. There are some other hints included (for free) on how to use your hand and fingers to measure the motion of the sun in terms of time or angles. The angles and scales are greatly exaggerated for illustration purposes. Remember that the Earth's atmosphere is comparable in scale to the skin of an apple. 

My Thomson friend offered another very plausible suggestion. The glow could even be from the full moon rising above the eastern horizon as the sun set in the west. The light reflected from the face of the moon would pass through a long atmospheric path. The light illuminating the atmosphere and forward scattered (Mie) to the artist's eyes would be tinted toward the yellow hues. The full moon would be located behind the cloud in the lower portion of the yellow circle. Please take another look at  "CSI 1. Looking East at Sunset" and you might now notice a faint full moon included in that graphic. 

Brilliant suggestion my friend! I believe this completes the Creative Scene Investigation of this masterwork which is not much larger than a postcard. How much science could Tom paint on a panel? Lots! 

Tom under the Anticyclonic Companion of a
 weak and fast-moving weather system

In summary, the preferred solution is that Tom was looking easterly at sunset at a front-lit landscape. The cloud colours were augmented by the pinks of the Belt of Venus. A full moon rising early in the evening also explains the subtle, mysterious glow. The winds were southerly and Tom was near the warm front of a weather system. The conveyor belt conceptual model suggests that Tom was looking at the anticyclonic companion of the warm conveyor belt. The leading edge of such systems is shaped by a double anticyclonic deformation zone and patchy cloud on the trailing flank of the departing ridge of high pressure. Any significant weather and certainly the associated cold front were still to the west. The cloud cover over the western horizon was not enough to significantly restrict the illumination of Tom's view to the east implying that this was a rather weather event.

My Thomson friend also suggested that the location of this view closely matches one from a favourite campsite on Whitson Lake which is a widening of the Petawawa River.  The "North Branch Ranger Cabin" once occupied that campsite and a trail also ran through the location. The cabin was still there in the 1940s when they planned to string a telephone line from the Achray Deputy's Headquarters on Grand Lake. The cabin was probably standing in 1916 and would have provided a convenient location for Tom to paint.

The bright greens in Tom's painting suggest that the art was completed in early summer when the vegetation was lush. Tom would have started his Forest Ranger job and been travelling the area with his coworker Ed Godin from their base at Achray. The details of their trips from the early summer of 1916 are unknown although they did canoe through the area in that autumn.

Feature 1 in the above comparison around the Petawa Hills is Louie Creek.

The similarities between the view, painting and terrain are convincing and support the conclusion that the view was front-lit looking easterly at sunset. Tom was looking across the Petawa Hills with Louie Creek draining into Whitson Lake at the lower left of the painting. 

There is one last piece of evidence that needs to be considered. Let's consider another sunset from the same spring of 1916 for comparison and see how Tom handled the colours. Tom would have been using the same palette and quite likely an identical slate of oil paints for each work. 

In spite of being painted at possibly the same time, these two sunset paintings are very different. Tom was simply looking in different directions. Tom painted what he saw. 

There is a huge difference between looking away from the sun and into the light at sunset.

The view looking westerly from the Whitson Lake campsite is also quite convincing in its similarities to the terrain Tom painted looking into the light of the sunset. Those details are included in the next graphic.

The Algonquin forest has grown back from those days of logging and extensive fires. The details of the terrain that Thomson painted are now cloaked. The similarities presented almost allow us to look over Tom's shoulder as he painted, inspired by the beauty of the weather and nature. Of course, we will never know for certain...

Finally, J.E.H. MacDonald and Lawren Harris met in the Studio Building in the spring of 1918. Tom's paintings from the Shack had been stacked in the Studio Building. Harris and MacDonald planned to sort through Tom's art, make comments on the back and distribute what they felt were the best examples of his genius.  Both of these paintings were in that stack of panels and both display the "TT Estate Stamp". 

Patron Dr. James MacCallum funded the Thomson Estate Stamp which was designed by MacDonald

One of these friends identified this as a sunset painting (among many with very similar names) and that is worth a few extra points. I suspect they thought that Tom was looking into the sunset instead of away. Perhaps it was even Lawren who chose the name and might have been with Tom for these sunsets when they were painting together in late April of 1916. As my Thomson friend points out, "Lawren Harris received his commission at Camp Borden on May 5th, 1916, so presumably had returned to Toronto around the beginning of May, thus suggesting the time of the fishing trip was probably in the second half of April."

      "Sunset Spring 1916" as it would have appeared       
in Tom's Paint Box

Inscription recto: 

• l.r., estate stamp Inscription verso: 
• c.?, estate stamp; in graphite, 27 
• Private Collection, Vancouver Island 

Provenance:

• Estate of the artist 
• Ralph Thomson, Seattle as no. 2 of three sketches described in Martin Baldwin's list of 7 May 1937 as belonging to Henry Thomson, Seattle and as "Sunset, yellow green sky, clouds, blue green hills, lake in front," 
• Ruth Wilkins, Renton, Washington, by descent, 1970 
• Private Collection, Vancouver Island 

Apparently, this is one of ten paintings that Tom's younger brother Ralph (1880-1934) acquired as part of the estate. As noted earlier, of the paintings that went into his father's possession, each of Tom's siblings received ten works. 

The Thomson Brothers with Tom Harkness, Brother-in-Law. 
Thomas “Tom” J. Harkness was the husband
of Tom's eldest sister, Elizabeth.

The Creative Scene Investigation conclusion after all of this is that Tom Thomson painted "Sunset Spring 1916" from near the North Branch Ranger Cabin on Whitson Lake looking east-northeasterly (away from the blinding light) at sunset in early summer probably in the company of his coworker Ed Godin (not Lawren Harris and friends). Tom's creativity was on fire and after completing this panel, he simply turned to look westerly and observed "Spring Sunset, Algonquin Park, 1916".

This was indeed a very challenging Creative Scene Investigation to complete but the findings are satisfactory.  I described all of the possibilities in order to be complete. It is rare to find the best solution without some stumbling around and help from knowledgeable Thomson friends!  

Thomson really did accurately paint what he saw. Any deficiency is simply in my ability to convincingly explain what he witnessed. 

Warmest regards and keep your paddle in the water,

Phil Chadwick

PS: Tom Thomson Was A Weatherman - Summary As of Now contains all of the entries to date. 

PSS: Should you wish to have Creative Scene Investigation applied to one of Thomson's works that I have not yet included in this Blog, please let me know. It may already be completed but not yet posted. In any event, I will move your request to the top of the list. If you made it this far, thanks for reading! 

Tom Thomson's Moonlight Over Canoe Lake

Thomson's weather works from 1917 have mainly been CSI'ed. I will gradually include other, earlier art that was not included in the first pass for one reason or another. 

"Moonlight Over Canoe Lake" from 1916 offers a wonderful opportunity to revisit some very interesting and important meteorology. There is much more than meets the eye in this small plein air panel! Tom was painting what he observed and the weather never lies. This painting appears deceptively simple but includes refraction, diffraction and every component of the conveyor belt conceptual model... In short, it was a challenge for Creative Scene Investigation! I will use graphics to replace the thousands of words that might otherwise be required. Please read and look on...

Moonlight Over Canoe Lake
Alternate titles: Moonlight; Moonlight on Canoe Lake Spring 1916
Oil on wood panel 8 1/2 x 10 5/8 in. (21.6 x 27 cm)
Tom Thomson's Paint Box Size

Tom Thomson made a stop in Huntsville at the home of Winifred Trainor in mid-March 1916. Tom was on his way to Algonquin Park. He would stay at Canoe Lake until mid April when he would be visited by Lawren Harris, Lawren's cousin Chester Harris and Dr. MacCallum. Tom possibly painted "Moonlight Over Canoe Lake" during that period between visits or in early May and we might even deduce the probable day of the week. Tom would head to Achray on Grand Lake later in May to work the summer as a Forest Ranger.  

The title gives the general location of Tom's painting away. The terrain of Canoe Lake and hints included in other paintings will provide the details. The alternate title could be misleading - more on that later. 

Tom was painting from the water's edge looking southward across the expanse of the north basin of Canoe Lake. The signature islands appear almost in line with the more distant shoreline from his low, water-level perspective. The western shoreline of Hayhurst Point was possibly to Tom's left but he could have also been at the very tip of Hayhurst Point at water level and simply looking more to the south-southwest.

The moon was certainly the important subject for Tom in this plein air work. Tom was painting at around 9 to 10 pm during the Waxing Gibbous phase of the lunar cycle. The Waxing Gibbous phase is when the lit-up part of the Moon grows from the First Quarter Moon and lasts until the Full Moon and such a moon must rise in the evening hours. Officially the Waxing Gibbous phase lasts 7.38 days. The Waxing Gibbous phase that Tom observed was about six days ahead of the full moon. 

The full moon in March 1916 was on the 19th so Tom might have been on his way to Huntsville on March 13th to visit Winnie Trainor but he certainly would have not arrived at Canoe Lake to paint the March Waxing Gibbous moon. 

The April 1916 full moon occurred on April 18th implying the date of Tom's weather observation would have been around April 12th. 

The May 1916 full moon occurred on May 17th requiring May 11th as the date of the Waxing Gibbous phase that Tom observed. 

 

Here is where my Thomson friend comes to the rescue. 

Where is the ice? The answer is that Canoe Lake was ice-free on that moonlit evening and that can likely rule out the April 12th estimate for this painting as being too early. 

"This would seem to suggest it was not too early in the spring, as the ice usually goes off Canoe Lake around April 21 or so, give or take a few days in either direction.  Earliest recent date for an ice-free Canoe Lake is March 29, latest May 15, so quite a possible range." 

The ice-free status of Canoe Lake suggests that "Moonlight Over Canoe Lake" might have been painted at 9 to 10 pm on May 11th, 1916. 

But Tom had taken a job as a fire ranger and he was supposed to report for service on May 1st, 1916. It is unlikely that Tom was at Canoe Lake on May 11th, 1916? 

Tom's comings and goings in the spring of 1916 are also up for debate. Thomson did stop to see Winnie in Huntsville in mid-March. Lawren Harris received his commission at Camp Borden on May 5th, 1916, so presumably had returned to Toronto by train in early May. The painting and fishing trip that Thomson enjoyed with his friends likely occurred sometime in the last two weeks of April 1916. 

My Thomson friend states: "it is almost certain the fishing party travelled to the Cauchon Lakes by train.  One of the sketches from that trip appears to show a bit of rotten ice in the foreground, though in most of the sketches any water seems ice free."

The travels of Thomson in 1916 are still in question but my Thomson friend continues to unravel the likely movements of our artist. There is even a possibility that this painting was from the autumn of 1916 when Thomson was at Canoe Lake as described below. 

My Thomson friend notes: "Tom did write to MacCallum from Basin Depot on October 4th, but could have been laid off immediately on his return to Achray, then got on the train to head back to Canoe Lake."

Tom's October 4th letter:

Dear Sir — [...] The Country up here is just taking the fall colour and by the end of the week will be at its best.

Could you arrange to come up this week. [...]

Have done very little sketching this summer as I find that the two jobs don't fit in. It would be great for two artists or whatever you call us but the natives can't see what we paint for. A photo would be great but the painted things are awuful. When we are travelling two go together one for the canoe and the other the pack and there's no place for a sketch outfit when your fireranging.

We are not fired yet but I am hoping to be put off right away.

[...]

Yours truly

Tom Thomson

An October date for "Moonlight Over Canoe Lake" might satisfy all of the known constraints except... it does not leave much time for Tom to hike from Basin Depot to Achray (15km) and then return to Canoe Lake. Even if he received his notice immediately on his return, he would have had to pack up and wait for one of the three days a week the train passed through Achray. November 4th, 1916 was the next waxing gibbous moon. According to the published Tom Thomson chronology, Tom returned to the Shack in Toronto either in late October or early November 1916. When and perhaps even where Tom observed this moonlit scene is still up in the air ... so to speak. It might even be Grand Lake and the waxing gibbous moon of September 6th. Stay tuned. 

The blotchy style of "Moonlight Over Canoe Lake" is also more reminiscent of his art created later in 1916. Many issues of the season and even the year a particular painting was completed have been discovered within Thomson's catalogue raisonné. If only Tom had made just a few notes, he could have saved a lot of speculation. 

In any event, it is probable that on that Waxing Gibbous moon evening, there was a strong storm approaching - cirrostratus coming at us.. (also see "Wind Waves and Swells and Lines in the Sky")

The halo encircling the moon also grabbed Tom's attention and he included it in accurate detail. The refraction of light through the hexagonal ice crystals of cirrostratus clouds produces the classic 22° halo. The refraction through the ice crystals also splits up the rainbow colours of the sunlight reflected from the face of the waxing gibbous moon. Long-wavelength red light is refracted by a slightly smaller angle than blue so appears on the inside of the halo - just as Tom painted. 

Classic full moon 22° halo.  

The parallel rays of  light reflected

from the lunar surface refract within hexagonal ice crystals that comprise cirrostratus cloud. Only the crystals at 22° refract light to our eyes thus creating the circular halo. The rare 46° halo is much larger and fainter than the common 22° halo. The 46° halo forms when sunlight enters randomly oriented hexagonal ice crystals through a prism face and exits through a hexagonal base.

The 22° halo can be measured with your hand.  Stretch out the fingers of your hand at arm’s length. The tips of the thumb and little finger then subtend roughly 20°. Place your thumb over the sun and the halo will be near the little fingertip. The halo is always the same diameter regardless of its position in the sky. Sometimes only parts of the complete circle are visible depending upon the distribution of the hexagonal ice crystals and intervening cloud - just as Tom witnessed. 

One more point to illustrate that Tom was a genius in his observations especially when he had a brush in his hand. Tom even included the "minimum deviation" effect by the lighter and brighter brush strokes just inside the 22° halo. The effect can also be observed in rainbows which Tom also painted. Most rays of light are refracted through the wafting ice crystals at angles close to 22° to form the bright inner edge of the halo. 

Moonlight Over Canoe Lake

The science of the 22° halo is very interesting and worth repeating in a different series of graphics. Sometimes restating the point might make the connection and send the message home. The source of the light is identified as the sun and that is always true. The moon is simply acting as an intermediary reflector to direct that light for us to view at night and it becomes the "source". 

The Bernoulli Effect tends to keep the ice crystals falling
flat and held perfectly orientated for refraction and the 22° Halo.

The intervening altostratus cloud blocked some of the 22° Halo. The combination of cirrostratus and altostratus cloud are classic indicators of a warm conveyor belt - more on that later. 

Did you also notice the glow in Tom's painting around the moon? Corona are coloured rings that appear about the moon or sun. Corona results from the diffraction of light by spherical cloud droplets.  If the cloud droplets are of uniform size, a corona is colourful with blue-violet on the inside and red on the outside. These coloured rings may repeat themselves in progressively fainter shades further from the moon.

The angular size of the corona depends on the diameters of the cloud droplets - small droplets produce large coronae. For the same reason, the corona is clearest when the size of the droplets is most uniform. Reddish colours always occupy the outer part of a corona ring. The corona is much smaller than the 22° halo.

The cloud particles that produced Thomson's corona were not especially uniform in size as there was no obvious separation of colours. It would have been a challenge to include that level of detail in the oils anyway even if it had been there!

Summary of the above Creative Scene Investigation

The following video produced from the "Tom Thomson Was A Weatherman" presentation explains the white line of the "Moon" on the distant horizon of the lake. The surface area reflecting the moonlight to the viewer's eye actually increases significantly with distance. The ratio of glinting reflection to refraction into the water also increases with distance. The result is a bright line that was observed and recorded in so many of Tom Thomson's paintings. The animation gives an idea of how the PowerPoint presentation worked. The talking points would appear and then vanish as I finished explaining each. 

Now for the weather that can be deduced from the cloud patterns.

The cloud patterns in the above graphic were regular swell waves in the altostratus-type cloud with no strong evidence of lateral banding due to wind waves. This suggests that the col in the deformation zone pattern was overhead. The swell wave crests were also angled toward the southwest. This places Tom under the Cyclonic Companion of the Warm Conveyor Belt. 

Easterly winds of the Cold Conveyor Belt would be convergent and accelerate around Hayhurst Point perhaps explaining the bowed shape of the wave crests as recorded by Tom. Diffraction of the waves around Hayhurst Point could also explain that shape. In both instances though, the wind would have to be easterly. That was a lot of wind and waves for 9 pm in the evening!

Tom located at the gold star would have been looking up at the cyclonic companion of the warm conveyor belt (WCB) not very far west of the central axis of the WCB (the large red arrow).

A top-down satellite view of the orientation of the weather system and Tom's probable location within the context of the approaching storm might help. The same patterns can be generated in duckweed with a paddle. 

 

Inscription verso:

• u.l.c., inscribed, Canoe Lake - 1916 jm; 
• u.l.c., Moonlight $25 / Tom Thomson; 
• label, Gavin Henderson Galleries, 759 Yonge Street, Toronto, Moonlight - Canoe Lake / Tom Thomson 1916 / $300 Art Gallery of Hamilton (1992.22.1)

Provenance:

• Estate of the artist
• Gavin Henderson Galleries, Toronto
• Roy G. Cole, Hamilton, ON, by 1953
• Art Gallery of Hamilton (1992.22.1). Gift of Roy G. Cole, 1992

The assigned value for this painting jumped in leaps and bounds over the years. The initial assessment of $25 pencilled on the back of the panel supposedly in the spring of 1918 would equate to $616.47 in 2022 dollars. Recall that Tom's patron Dr. James MacCallum was in the habit of paying $15 (worth $369.88 in 2022) for those plein air paintings when one caught his fancy. I suspect Jim (J.E.H.) MacDonald initially assigned the $25 dollar estimate and he realized back then that this particular painting was indeed special and worth more! 

Roy Cole made a terrific purchase in 1953 for $300 (about $3377.28 in today's dollars and still a significant increase over the initial estimated value of $616). "Moonlight Over Canoe Lake"  would certainly fetch more than $1.5 million. By extension of the suspected J.E.H. MacDonald estimate of the relative value of this work in the spring of 1918, "Moonlight Over Canoe Lake" should probably fetch $2.5 million in the art auctions of 2023. 

If all you think about is money, then Lawren Harris was correct when he advised his wealthy friends to buy Thomson paintings. My desire is that you should ponder more about Tom's art than currency or how he died. What really matters is how he lived!

The beauty of the science and the meteorology in this weather observation means a lot to me and certainly took a while to CSI. Tom painted a waxing gibbous moon at 9  to 10 pm. The date could have been Thursday, October 5th, 1916 as a vigorous autumn storm approached Canoe Lake. The details of the 22° halo and the glow of the corona were carefully and accurately observed. Tom was experimenting with a blotchy approach to thickly applying paints to his panels in 1916 and "Moonlight Over Canoe Lake" was one of the early panels to demonstrate that approach. Tom was not making this stuff up... Tom was living life and enjoying it immensely. And he did all of this on a small wooden panel measuring only 8 1/2 by 10 5/8 inches. Tom could have been eager to pick up the brushes again after a summer of fire-ranging!

Warmest regards and keep your paddle in the water,

Phil Chadwick

PS: Tom Thomson Was A Weatherman - Summary As of Now contains all of the entries to date. 

PSS: Should you wish to have Creative Scene Investigation applied to one of Thomson's works that I have not yet included in this Blog, please let me know. It may already be completed but not yet posted. In any event, I will move your request to the top of the list. If you made it this far, thanks for reading! There is a lot of science in this small panel and I wanted to cover most of it...