Story and photos by Kristen Cart
We took a number of elevator detours on our return home from a Nebraska trip, where we delivered our daughter to her summer veterinary camp. During the four-day program presented by Oxbow Animal Health, she learned the inner workings of a cow, and lovingly operated on and sutured a stuffed bunny. Apparently there is no such experience offered to children in Illinois.
The trip home was a meandering route with a number of switchbacks, with elevators built by Tillotson Construction, of Omaha, spaced every few miles. One elevator stop on our sojourn was Dike, Iowa, in the central part of the state. This fascinating site was the last one we saw before the light failed. We were racing a line of weather, and as the sun sank the clouds built and made for very flat light.
It is enlightening to see an elevator complex in person and compare it with an early photograph. The changes wrought in almost seventy years can be surprising, but even more unexpected can be the features that remain the same.
At Dike, you immediately notice a wooden structure behind the main structure. Strangely, it does not appear to be the same elevator that appears in the old photograph. Why would the co-op replace a wooden elevator with another one? The obvious answer would be a fire, but if wood was obsolete, why continue to build with that material?
In my travels, I have rarely come across a wooden elevator that was built before the 1940s and still in use today. Technology rendered the old ones obsolete, and wear and tear made them difficult to operate. Fire also took many of them. Now, wooden elevators built as late as the 1970s are coming down as more valuable uses are found for their wood, and as regulations make them harder to license.
Dike’s concrete elevator was built in 1946, and it came with an unusual (for Tillotson) headhouse. In the one place where we found a similar example, at St. Francis, Kan., the elevator built by J. H. Tillotson, Contractor, sported a rectilinear headhouse. Though it was replaced much later, early pictures show that the St. Francis headhouse was built in that style.
Both the old Omaha company and its later offshoots preferred curved architecture because it was more economical to build.
So the Dike elevator was a non-typical construction, and we know from its early photo that it started out that way. Since we have no record of it in our Tillotson company records, we have to assume it was built by another company. But the Omaha company led by Reginald Tillotson built the annex.
Tillotson Construction arrived on scene in 1949 to add the annex just three years after the main house was built. In the late 1940s, when elevators were filled just as fast as they could be built, annexes sprung up almost before the concrete cured on the original elevators.
The Dike, Iowa, annex specifications
Capacity per plans (with pack): 200,700 bushels
Capacity per foot of height: 1,859
Reinforced concrete per plans (total): 1,255 cubic yards
Plain concrete (hoppers): 3 cubic yards
Reinforcing steel (including jack rods): 73.56 tons
Average steel per cubic yard of concrete: 117.2 pounds
Steel and reinforced concrete per plans:
Below main slab: None
Main slab: 23,665 pounds steel and 218 cubic yards concrete
Drawform walls: 94,152 pounds steel and 880 cubic yards concrete
Work and drying floor: None
Deep bin bottoms: None
Overhead bin bottoms: 18,156 pounds steel and 56 cubic yards concrete
Bin roof: 4,223 pounds steel and 32 cubic yards concrete
Scale floor: None
Distributor floor: 3,570 pounds steel and 30 cubic yards concrete
Cupola roof: Steel included in above amount, and 21 cubic yards concrete
Misc. (Boot, leg, head, track sink, steps, etc.): 500 pounds steel and 4 cubic yards concrete
Attached driveway (for Dike plans, lower tunnel indicated here): 363 pounds steel and 14 cubic yards concrete
Main slab dimensions: 46 1/2′ x 68′
Main slab area (actual outside on ground): 2,955 square feet
Weight reinforced (total) Concrete (4000 pounds per cubic yard) plus steel: 2,583 tons
Weight plain concrete (hoppers 4000 pounds per cubic yard): 6 tons
Weight hopper fill sand (3000 pounds per cubic yard): 25 tons
Weight of grain (60 pounds per bushel): 6,021 tons
Weight of structural steel and machinery: 5 tons
Gross weight loaded: 8,640 tons
Bearing pressure: 2.93 tons per square inch
Main slab thickness: 24″
Main slab steel (size and spacing): 1″ diameter, 5 1/2″ o. c.
Tank steel and bottom–round tanks (size and spacing): 5/8″ diameter, 9″ o. c.
Lineal feet of drawform walls: 400′ (no drive)
Height of drawform walls: 120′
Pit depth below main slab: None
Cupola dimensions (outside width x length x height): 13′ x 93′ x 8′
Pulley centers: None
Number of legs: None
Distributor Floor: None
Track sink: None
Full Basement: Yes
Electrical room: In elevator
Driveway width: None
Dump grate size: None
Columns under tanks: 4 columns 16″ square
Boot Leg and Head: None
Top conveyor: 30″ belt at 500 bushels per minute; 7,800 bushels per hour; 10 horsepower drive; Howell tripper.
Bottom Conveyor: 24″ belt at 600 bushels per minute; 5,800 bushels per hour; 7 1/2 horsepower drive
Also built: Extended driveway on elevator