The first response to the post was "I’m guessing Dean’s Park or the boulder doesn’t exist anymore?" which is an understandable response.
I grew up in Charlestown, which was part of Westerly until 1738, and I hiked the management areas and trails all over the area. I had never heard of a Dean's Mill Park near Westerly either.
There are other images on eBay of that particular postcard, two in black and white and postmarked with the date of 1906. Hippo.com, another online purveyor of antique postcards, had one in color with a long written note on the back, but without a postmark or date in the text. Then there were two other postcard's, one captioned "Dam at Dean's Mill Park" from c. 1905, and a different "Dean's Mill near Westerly RI" dated September 1909 (pictured below):
But neither Dean's Mill or Dean's Mill Park come up in a Google maps search of Westerly. I thought it might show up on a late 19th / early 20th century map, but the nearest map in time to the postcard, the 1895 Richards & Everts map of Westerly is focused on what is the "downtown" area of Westerly and Pawcatuck and there is no Dean's Mill there. But in my survey of sites for the "Lost Mill Towns of South County" project, I had never read about a Dean's Mill in any of the several other mill villages around Westerly.
A search of the RIHPHC March 1978 survey of Westerly makes no mention of Dean's Mill either, and unlike the Richards & Everts map, that is a review of the history and architecture of the entire town, not just the downtown area. And while the RIHPHC surveys are not one hundred percent foolproof, that a) I had never heard of it in 50+ years of hiking around the area, that b) I couldn't find Dean's Mill on any Westerly maps, and c) that it was not in the state survey or in any other research I've done -- confirmed my suspicion that despite the caption this postcard image was not of any place in or near Westerly.
But that is a rather unique glacial erratic near a stone wall -- and the image, that frame of reference, everything in there -- should still be there unless it was blasted out and removed for a housing development or to widen the road.
The view seen from the postcard is easily recognizable. Its just a matter of figuring out where to stand to see it, if not "near Westerly."
Then I found another clue -- there's a Dean's Mill School on Dean's Mill Road not in Westerly but one town over, in Stonington CT. The northern terminus of Dean's Mill Road begins on Pequot Trail/RT. 234, then it travels east of Deans Reservoir, which was created by damming Cobbs Brook. The mill pond is bisected by Rt. 95 (and becomes Mystic Reservoir south of the interstate), then Dean's Mill Road crosses Mistuxet Ave / Pellegrino Road (it's a weird intersection) and ends in the south on Flanders Road. The northern section of Dean's Mill Road that runs past the reservoir is very narrow and you can't "drive down it" on Google Maps, though it has a town speed limit sign of 15 MPH and another sign warning of a "Narrow Road" and so it must be maintained to some degree by the town of Stonington. The section of Dean's Mill Road south of the intersection with Mistuxet Avenue and Pellegrino Road is much wider and is where Dean's Mill School is located.
There is no Dean's Mill Park on Dean's Mill Road but there but there is a Deans Mill Preserve off Jerry Browne Rd on the western side of the reservoir (in red on the AllTrails map below). The park in the postcard may very well be part of this preserve -- AllTrails doesn't say. But where to stand to see the frame of reference of the postcard? We are much closer to answering that question now!
Given this postcard was printed by assorted RI printers, the caption "Near Westerly RI" for a scenic park in Stonington makes sense. Rhode Islanders and tourists visiting RI would be more likely to purchase and use the postcard if it said the image was "near" a well-known central place in Rhode Island than if it was labeled "Stonington Connecticut."
Below is an 1868 map from An Atlas of New London County by Beers, Ellis & Soule of the area in the AllTrails map - (there is a higher resolution version of this map here). What is Dean's Mill Road follows the exact same track on the 2022 and 1868 maps.
The reservoir area is circled in red -- the mill pond is much much smaller than the Mystic/Dean's Mill Reservoirs are today and at the southern end there is a point symbol labeled "G. Mill," for grist mill. My guess based on AllTrails and the maps was that Dean's Mill was a manufacturing concern located on the western side of Copps Brook opposite from the grist mill, and was in business sometime after 1868 and before 1906.
Then as I started putting all these pieces together in this blog post, it came to me that a search of the actual place, Dean's Mill Park + Stonington Connecticut might yield much better search results. That search proved to be much more fruitful, as one might imagine.
I quickly found the The Quiambaug/Mistuxet Valley website, a very thorough look at this area of Connecticut put together by one Bryan A. Bentz . This had all the information I was hoping to find about this mill site:
Built "long before the Revolution" according to Grace Wheeler ... the home of the Stanton Brothers is south of Pequot Trail, along what was once a public road between Pequot Trail and the upper dam across the reservoir. The road is now a very long driveway; I expect few have intruded enough to see this magnificent house.
|The Stanton Bros. home, between Pequot Trail and the upper dam |
Image credit: qb.mindhenge.org/structures.html
Grace mentions Frank Stanton's large family (five sons and four daughters: "...a great part of the pleasure of the nearby society would center about them; many a sleighing party and dance was quickly gotten up". She goes on to further describe the road down to the upper dam:
The path from the Stanton House to the Dean's pond is a most romantic, winding road. This has been an historic place in the town's history. The old house at Deans Mills was built by James Dean Jr., in 1700, and it was burned down in 1848. Mr. James Dean Sr., lived at Quiambaug, just east of the Quarry ledges. Very near this second Dean house was an immense rock, which still stands a silent and immovable reminder of bygone days. James Dean was a blacksmith and had also learned the trade of fulling and dressing woolen cloth. He built a dam and fulling mill on Mistuxet brook and he and his son, James Dean, built another which was enlarged in 1807 into a factory building, with grist mill and new machinery for cloth dressing, wool carding and for the manufacture of cotton and woolen goods, by Mr. John Dean and son, James. Here was where many young men of the first families were employed...
The Dean pond, woods and the old Lover's Lane are now again made prominent features of the town. The pond is the head of the Mystic Valley Water Co., from whence the villages are supplied with water...
The reservoir has effectively changed the water level so that the area doesn't look the same nowadays, though when there is a drought, or some other reason to drain down the upper reservoir, the old foundations of the Mills may be seen..."
Here are several pertinent images with the captions quoted from the Quiambaug/Mistuxet Valley site:
|"Looking at the upper dam from the South; the channel and walls |
visible are now all under water."
Image credit: qb.mindhenge.org/structures.html
|"The structures of Dean's Mill, where the upper dam is now, just north of I-95. |
About the only recognizable feature is the large stone hill at the right."
Image Credit: Grace Wheeler Old Homes In Stonington" p.34
On a separate page of the Quiambaug/Mistuxet Valley website, there is more information about Dean's Mills and the image of the mills (above):
...[According to the image above] from Wheeler's "Old Homes in Stonington", pg 34; the house was built in 1700. The large rock on the right suggests this is near where the upper dam is now, just north of I-95. The text of the book introduces this topic by mentioning the lane from the Stanton's house, which would place this at the upper dam. After the I-95 construction and various rounds of repair to that dam, little is left to match against this image.
Then the webpage provides some more history about the Deans and their mill activities:
...James Dean of Taunton came to Stonington, and his son James Jr. established a fulling mill:
James Dean, Jr., did not confine himself to blacksmithing, but learned the business of fulling and dressing woolen cloth, and for that purpose erected a fulling-mill on Mistuxet Brook, afterwards known as Dean's Brook, about one-third of the way from the old post road down to the Dean's Mills. There he continued both branches of business until his son, John Dean, reached manhood, when he and his father built a new dam and erected another fulling-mill near his dwelling-house, where the dam now crosses the brook. After this arrangement was effected they devoted their time and attention to cloth-dressing, wool carding, and for the manufacture of cotton and woolen goods were obtained... James Dean continued in business until 1830, when he retired.
...The "old post road" we now call Pequot Trail, and "Dean's Mills" is, as described above, at the "upper dam" just north of I-95. This places the original fulling mill 2/3 of the way between them. Recently I received a number of photographs of this location, only possible because of an extensive drought...
I am not going to repost those photographs, which were taken of what was left of Copps Brook in 2016 during that year's drought, but these photos clearly show there is nothing left of the mill seat except piles of rocks, the ruins of what was once the upper dam before the highway was built. The foundations to the mills could be located -- they are either buried under debris and sediment or they are long gone, torn up in the construction of Interstate 95.
And finally, here is where we came in. There on the Quiambaug/Mistuxet Valley website was the image from the postcard from the Facebook post, but this postcard's caption comes with a more accurate "near" address:
According to the Quiambaug/Mistuxet Valley website,
"the [p]recise location [of the glacial erratic pictured above] not known, but the large boulder may be the rock on the western side of the reservoir just north of the upper dam."
I plan to take a motorcycle ride over there in the near future and see if I can find the boulder in the postcard. Unfortunately, there is no point looking for the foundations Dean's Mill, as they were destroyed by the construction of Route 95. My guess earlier in this quest, that something should still be there unless it was "blasted out" to build a road was not far off the mark. But while I'm there I will take a stroll along the Deans Mill Preserve, which may the closest thing we have to going to Dean's Mill Park in the 21st century.
 Grace Denison Wheeler, "Old Homes In Stonington" 1903 (reprinted 1930), The Mystic Standard. Available from the Stonington Historical Society (Higginson Book Company reprint)
 Bryan A. Bentz, The Quiambaug/Mistuxet Valley A History of a Valley and its Two Ridges. https://qb.mindhenge.org