Possible Clues:

• Sufficient to stop the snake on the street
• Walk hesitatingly with snake on surface of path
• That's enough to make a snake stop on the road
• Bituminous road dressing
• Mixture of tar and gravel for paving
• That's enough to make one 17 down stop on the street
• Used when a path's relaid round top of the lane
• Get the serpent to stop 12 across
• Garage surface
• Metal model construction set