Originally, headboxes were open to the atmosphere ( open headbox ) .是什么意思？

Originally, headboxes were open to the atmosphere ( open headbox ) .

通常, 开放式头箱与大气 相通.

originally

adv. 起初，原来，独创地，独出心裁地，自来，本；

例句
Sunset Boulevard was originally conceived by Wilder as an astringent satire on Hollywood.
怀尔德最初是想把《日落大道》拍成一部对好莱坞的辛辣讽刺片。

were

be的过去时复数和第二人称单数形式，有时代替 was,用于条件从句、动词 wish 之后等；

例句
Shops, houses, and vehicles were set ablaze.
店铺、房子和车辆全都陷于火海。

open

adj. 敞开的，开着的，公开的，公共的，坦率的，有议论余地的；vt.& vi. （打）开，开始，睁开，启动；n. 户外，野外，空旷，公开；vi. 使打开，展示，显现；vt. 张开，开放，开张营业，为（建筑物）揭幕；

例句
Some banks make it difficult to open an account...
一些银行把开户弄得很麻烦。

to

prep. 向，朝着，到，关于，属于；adv. 朝一个方向的，到某种状态，关闭；

例句
I suggest you leave it to an expert...
我建议你把它留给专家来解决。

the

art. 指已提到的人（物），指说话人与听者已知的人（物），用于独一无二的事物前，与形容词最高级和序数词连用；

例句
He did have a real knowledge of the country...
他对该国的确知之甚多。

atmosphere

n. 大气，空气，大气层，风格，基调，气氛；

例句
There's been an atmosphere of anticipation around here for a few days now...
几天来这里一直有一种满怀期待的气氛。

headbox

压头箱；

例句
Throttles dense solutions of paper mill stock for headbox flow control, etc.
用于压头箱流体控制的造纸厂原料的稠密流体节流, 等等.