They are placed 20 feet off the ground on poles spaced every four city blocks.
One study found that students studying foreign language vocabulary can get just as good long-term retention from having learning sessions spaced out every two months as from having twice as many learning sessions spaced every two weeks.
In Pennsylvania, the sandstone inns-seeds of villages some of which thrived and expanded while others became a decaying huddle-were spaced every three miles or so, the distance a man could walk in an hour or a team of horses could pull a farm wagon on a summer day without needing to be watered.
Even in Hangzhou, though – with 3,000 docking stations spaced every few hundred metres – some new dockless share bikes are popping up, mostly provided by the smaller copycat firms.
Gracie's own house, a two-story clapboard, was one of a string of country houses spaced every few hundred yards along the East River, put up by the Joneses, the Schermerhorns, the Rhinelanders and others.
A metal grid of 12 cm×16 cm, with bars spaced every 8.5 mm was hung 50 cm above the floor.
Use small dowels spaced every foot or two along the row, with twine tied between, to give the plants something to lean on.
Using two-by-six studs spaced every 24 inches, instead of two-by-fours at 16-inch intervals, created deeper cavities for insulation.
Because of the low capture rate at Catie, I began to worry that the grid layout, 500 meters square, with two traps spaced every 50 meters, wasn't working well.
We designed a Roche Nimblegen High Density (HD2) tiling array with 1.98 million probes spaced every 60 nucleotides and covering the entire sequenced portion of the Arabidopsis genome.
