想必大家开车时都遇到过这玩艺儿，特别是开土路和小路，猜猜看这玩艺叫什么？干啥用的？在中国俺没见过，只在北美看到。

       如果有人觉得这道猜猜看很简单，可千万别马上说出来了，您就先憋两天吧，谢谢！（周一公布答案，南雪北飘可以今天说出来了，先给你戴朵小红花。）

（答案：TEXAS GATE.  A “Texas Gate” refers to a grid which prevents cattle and horses from entry while allowing the driver of a vehicle to pass through without having to open gates. The term is not to be found in many dictionaries or encyclopedias; it appears to have originated with the northern migration of cattle—the great cattle drives from Texas in the late 1870s—and is in common usage in the northern American western states and the Canadian west. In Texas, these gates are called “cattle guards.” In the SARM 1997 Resolution No. 15, both terms are used and “Texas” is spelled with a lower case “t”: “Whereas, many individuals and oil companies install cattle guards, commonly known as texas gates, on road allowances without approval from council.” ）

       图1：全貌。
      

       图2：局部。这个是方钢，上图是圆形钢管，大同小异。