I have searched through the literature on Moor Street for the water capacity of the tank but with no luck. However, Tyseley has a two tank design holding 96,000 gallons while Earlswood's was only 12,000 gallons. The latter size would be enough to top up several locos after climbing up from Stratford upon Avon. Tyseley, on the other hand was designed to be able to rapidly refill all the locos on shed. Moor Street's needs would fit in between these two extremes. Looking at the footprints of Moor Street vs Tyseley, I would guess that 36,000 gallons could have been the capacity at Moor Street, though that is comparing apples to oranges..
My footprint derived from the 25" scale map looks to be a bit too long, a purely subjective comment. There is a
Fire Insurance Map from 1937 of Moor Street on Warwickshire Railways but unfortunately the boundary cuts through the plan of the tank, thwarting any confirmation of its length. No end of searching today has found the 1937 revision on line.
I have taken the photo found by Yorkshire Dave on Flickr and tweaked its exposure, contrast and shadow settings to get to this:
The supports are clearly of the North Warwickshire Line design and they are inset from each end. The four supports can easily be identified by the location of the diagonal supports, leaving other vertical components to be considered. I am wondering if there were two large diameter downpipes, one heading off to each of the water cranes?
The post processing (if it can be called that) has also brought out the vertical rivet patterns on the tank walls and these are identical to those at Earlswood. The panels number 4 across the end at Moor Street while there are only three at Earlswood. Earlswood has 5 panels along the tank side but there is no evidence for that number on the Moor Street tank due to masking by the signal.. Earlswood has 7 cross supports sitting on the main support beams but it is impossible see how many might have been present at Moor Street. The height of the tank walls appears to be more than the height of the sides of the Moor Street tank, but it equally possible the both tanks actually have the same vertical dimension. Again, the supports at Earlswood are undoubtedly shorter than Moor Street because the tank is mounted on an embankment above the platforms.
Next, a check on the water tank at Henley in Arden. It compares very closely to that at Earlswood, having similar layout and dimensions. It is also perched on an embankment so has shorter supports. Scaling the footprint from the 25" map of the area gives a dimension of approximately 20ft length by 12ft width. Earlswood scales off at much the same. I am beginning to wonder, however, just how accurate the rectangles represent the "truth" on the ground or were they "representative shapes".
Going back to Moor Street, the scaling gives a footprint dimension of 36ft long by 16ft wide. The widths compare nicely, 3 panels = 12ft, 4 panels = 16ft. It also tells us that the panels were probably a standard width. So, Earlswood's length is 5 panels which should give a length of 20ft. Check!
So how many panels should there be on a Moor Street tank side? Nine. And how many cross supports on the main support beams? ( 9/5 ) x 7 = 12.
Edit to add that the photo in Post 775 has 9 suggesting the cross beams are approximately 4 ft apart.
Next, the height of the Moor Street tank walls. Using the excellent near side on view of Earlswood, the ratio of width (4ft) to height is about 0.5, meaning the walls are 8 ft high. The ratio on the end wall of Moor Street's tank is approximately the same at 0.5, which implies the reasonable assumption that they are standard panel sizes, at least for the North Warwickshire Line.
Finally, the volume of the tanks. We know that Earlswood (and therefore probably Henley in Arden) was a 12,000 gallon tank. This relates to a volume of (20 x 12 x 8 = 1920) cubic feet. 1 cubic foot of water contains around 6 imperial gallons, which would be 11,520 gallons. That is close!
So, by extrapolation, Moor Street's capacity may have been around (36 x 16 x 8 = 4608) cubic feet, giving an imperial gallon capacity of around 27,500 gallons. That would appear to be about right for the needs of a small terminus station with mainly large tanks and panniers plus the occasional tender locomotive.
How reliable is all of the above?
1. I think the process has given good confidence that the Moor Street water tank was a larger cousin of the two water tanks on the North Warwickshire Line that were constructed during the same time period.
2. The enhanced photos of all three tanks show good similarities of design, with the exception that Moor Street's foundation was at track level, not on a raised embankment. Hence the longer supports and bracing at Moor Street.
3. Using the 25" scale maps has introduced a significant margin of error IF you don't accept the draftsmanship of the rectangular footprints to be accurate. Having three rectangles and a known calibration (St. Martin Church in the Bull Ring) that "make sense" does give optimism.
4. All the photos of Moor Street water tank are close to end on, so there is no easy way to check on the length of the tank, the number of panels or the number of cross supports.
Conclusion
I think I can be brave enough to start drawing plans up for the water tank.