both the tow vehicle 49 and trailer 1 39 are on flat ground so that no portion of chains 27a and 27b will 34 bend around 34 edge 42 of trailer body 3 39 if the tow vehicle begins to ascend a sharp incline relative to the ground on which trailer 1 is supported this obviously could cause undesired actuation of the trailer brakes and undue stresses on various pivot points of steering mechanism 1 in the embodiment of fig1 a the distance between the centers of holes 69 and 65b fig2 a on draw bar 35 is six and one half inches hole 65a is the same distance on the opposite side of hole 69 the length of tongue 39 is approximately sixty seven and one half inches when tow vehicle 49 is exerting a forward force on tongue 39 although this dimension is not critical the distance between the centers of pivot point 23 of primary steering arm 25 and pivot point 25a is 15 inches the line between pivot points 23 and 25a is inclined rearward twelve and one half degrees with respect to axle 7 the perpendicular distance between longitudinal axis 110 which passes through the center points of pivot point 23 pivot ball.