Show At a speed o of 60 miles mlles an hour the pistons ot of o the ordinary auto auto- automobile automobile automobile mobile engine are traveling traveling- at arate a arate arate rate of o 30 miles every ery 60 GO minutes Yet they reverse erse their direction about every ever five the Inches ot of o the way That this process can te fie t t e continued without audible knocking o of the pistons against the cylinder walls or banging of the connecting rod bearings Is one of ot the greatest single achievements of ot modern engineering |