the British steamer "Rumney" crashed into the French ship "Frigorifique."

英國蒸汽船 Rumney 撞到了法國船 Frigorifique

Seeing their ship filling with water,

法國船員看著自己的船慢慢注入海水，

the French crew climbed aboard the "Rumney."

只好爬上 Rumney 求生

But as they sailed towards the nearest port,

但就在他們航行到最近的港口途中，

a silent form suddenly emerged from the fog:

濃霧中突然出現一艘寂靜無聲的船：

the abandoned "Frigorifique."

就是被遺棄的 Frigorifique

It was too late to turn,

此時已經無法轉彎避開，

and the impact was enough to sink the "Rumney."

撞擊的力道導致 Rumney 沉船

As the sailors scrambled into the lifeboats,

而在水手們匆忙混亂的爬上救生艇後，

the empty "Frigorifique" sailed back into the fog,

無人的 Frigorifique 又開回了濃霧中，

having seemingly taken its revenge.

像是成功復仇一般的離去

In reality, the French sailors had left the engines running,

實際上，法國船員在逃難之餘並沒有停止船的機件與馬達運轉，

and the "Frigorifique" sailed in a circle

所以 Frigorifique 一直在繞圈子打轉，

before striking the "Rumney" and finally sinking.

直到遇見了 Rumney 發生撞擊後才沉船

But its story became one of the many tales of ghost ships,

不過這個故事仍然成為幽靈船的傳說之一，

unmanned vessels that apparently sail themselves.

因為沒有人在船上，竟然還能航行

And although they've influenced works like "Dracula"

雖然這些故事衍伸出像是「德古拉」

and "Pirates of the Caribbean,"

和「神鬼奇航」等電影，

crewless ships aren't the product of ghostly spirits,

自動行駛的船並非由鬼怪幽靈操控

just physics at work.

只是一個物理現象

One of the most famous ghost ships was the "Mary Celeste",

最有名的一艘幽靈船叫做「瑪麗‧賽勒斯特號」

found sailing the Atlantic in 1872 with no one aboard,

1872 年被發現在大西洋獨自航行，而船上空無一人，

water in its hold,

且平穩航行，

and lifeboats missing.

但救生艇都消失了

The discovery of its intact cargo and a captain's log that ended abruptly

船上全新的貨物和船長匆促結尾的日記導致

led to wild rumors and speculation.

各式各樣的謠傳和臆測出現

But the real culprits were two scientific phenomena:

但是背後的操控者實際上是兩個科學現象：

buoyancy

浮力

and fluid dynamics.

還有流體動力學

Here's how buoyancy works.

我們來看看浮力是怎麼運作的

An object placed in a liquid displaces a certain volume of fluid.

若將物體放在液體中，沉在液面下的部分會排開相同體積的液體

The liquid in turn exerts an upward buoyant force

同時，液體會對物體施加向上的浮力，

equal to the weight of the fluid that's been displaced.

這個力量和被排開的液體重量相等

This phenomenon is called Archimedes's Principle.

這個現象稱為阿基米德定律

Objects that are less dense than water,

物體密度比水小的時候

such as balsa wood,

像是輕木條

icebergs,

冰山

and inflatable rafts always float.

和充氣橡皮艇一定會浮起來

That's because the upward buoyant force

就是因為向上的壓力 (浮力)

is always stronger than the downward force of gravity.

比向下的重力還要大

But for objects or ships to float when they're made of materials, like steel,

但是船或其他可以浮在海上的物品，若是用鋼鐵製成

that are denser than water,

或是其他密度比水還大的材質

they must displace a volume of water larger than their weight.

他們就必須排開比自身重量還要大體積的水量

Normally, the water filling a ship's hull would increase its weight and cause it to sink -

一般來說，當水注入船身時，船的重量就會增加而導致沉船

just what the "Mary Celeste's" crew feared when they abandoned ship.

這也是為什麼水手們會逃離瑪麗‧賽勒斯特號

But the sailors didn't account for fluid dynamics.

但是水手並沒有想到流體動力學

The water stopped flowing at the point of equilibrium,

當不斷注入船身的水和破洞等高時

when it reached the same level as the hole.

就會停止

As it turned out, the weight of the water wasn't enough to sink the ship

最後結果，注入船身的水之重量並不足以讓船沉到海底

and the "Mary Celeste" was found a few days later

幾天後瑪麗‧賽勒斯特號被人發現

while the unfortunate crew never made it to shore.

但逃離它的水手卻沒有成功上岸

Far stranger is the tale of "A. Ernest Mills,"

更離奇的是另一艘船 A. Ernest Mills

a schooner transporting salt,

這是一艘專門運輸鹽巴的船

whose crew watched it sink to the sea floor following a collision.

船員眼睜睜看著它在碰撞後沉到海底

Yet four days later, it was spotted floating on the surface.

但是四天後，卻被發現好好地在海上

The key to the mystery lay in the ship's heavy cargo of salt.

真正的原因其實和船上載的大量鹽巴有關

The added weight of the water in the hull made the vessel sink,

一開始沉船的原因的確是因為注入的海水讓船身變重

but as the salt dissolved in the water,

但是船身的鹽巴融於海水後

the weight decreased enough

重量大幅減輕

that the force of gravity became less than the buoyant force

重力小於浮力

and the ship floated back to the surface.

所以船又浮出海面

But how do we explain the most enduring aspect of ghost ship legends:

但是我們究竟該如何解讀幽靈船傳說最詭異的一點：

multiple sightings of the same ships hundreds of miles and several years apart?

目擊者會在距離沉船地點很遠的地方再次看見同一艘船

The answer lies in ocean currents,

秘密就藏在洋流裡

which are like invisible rivers flowing through the ocean.

洋流就像是藏在海底，看不見的河流

Factors, like temperature,

生成的原因包含溫度

salinity,

鹽度

wind,

風向

gravity,

重力

and the Coriolis effect from the Earth's rotation

還有來自於地球自轉的科氏力

create a complex system of water movement.

讓水流系統變得複雜

That applies both at the ocean's surface and deep below.

不僅會影響海平面，也會影響深層的海底流動

Sailors have always known about currents,

水手都知道洋流

but their patterns weren't well known until recently.

但是最近才更加了解洋流的運作及影響

In fact, tracking abandoned ships was how scientists determined the shape

事實上，追蹤這些棄船在早期是科學家找出

and speed of the Atlantic Gyre,

大西洋環流的規模和速度

the Gulf Stream,

墨西哥灣流

and related currents in the first place.

還有其他相關的洋流的重要方法

Beginning in 1883, the U.S. Hydrographic Office

1883 年開始，美國的水道測量局

began collecting monthly data that included navigation hazards,

開始每個月都蒐集一些數據，包含航行的風險

like derelict ships, whose locations were reported by passing vessels.

像是無人船的位置通常由經過的船隻回報

So abandoned ships may not be moved by ghost crews or supernatural curses,

無人船會移動其實和幽靈或是其他超自然詛咒無關

but they are a real and fascinating phenomenon

不過它們的確是真實且令人感興趣的現象

born through the ocean

誕生於海上的秘密

and kept afloat by powerful, invisible, scientifically studied forces.

持續由有力、看不見的科學力量航行