海螺裏聽見的當真是大海的聲音

Do you remember trying this as a kid -- Holding one of the seashells you grabbed as a souvenir up to your ear? It seems like no matter how far away from the ocean you are, you can still hold a seashell up to your ear and hear the roar of the waves rolling onto the shore. The best shells for producing this sound are the large, spiral conch shells.

你是否記得在小的時候，你把那個拾來做紀念的海螺貼到耳邊，不管你離大海多遠，似乎還是能從海螺裏聽見海浪衝刷沙灘的響聲。最適合拿來“聽海”的，莫過於大隻的海螺了。

Some people have suggested that the sound you hear from the seashell is the echoing of your blood rushing through the blood vessels of your ear. That is not the case. If that were true, then the sound would intensify after exercising, since your blood races faster after exercising. However, the sound is the same even after exercising.

有人認爲從海螺裏聽見的這種聲音是耳朵附近的血管裏血液流動的回聲。如果這種說法是對的，那麼在運動過後，這種聲音應該會變得更響，因爲這時人體的血液循環加快了。但事實並非如此，也就說明之前的說法站不住腳。

Others say that the whooshing sound inside the shell is generated by air flowing through the shell - air flowing through the shell and out creates a noise. You'll notice that the sound is louder when you lift the shell slightly away from your ear than it is when the shell is right against your head. However, this theory doesn't hold true in a soundproof room. In a soundproof room, there is still air, but when you hold the seashell to your ear, there's no sound.

另有人認爲，這種嗖嗖的聲響是由海螺裏的空氣流動產生。如果你把海螺從耳邊稍稍地挪開一點，你會發現這時的聲響要比海螺貼在耳旁的時候來的更大一些。不過，這個理論在同樣被證明是錯誤的。在一件隔音的房間裏，空氣照常流動，但此時把海螺貼在耳邊並不能聽到聲響。

The most likely explanation for the wave-like noise is ambient noise from around you. The seashell that you are holding just slightly above your ear captures this noise, which resonates inside the shell. The size and shape of the shell therefore has some effect on the sound you hear. Different shells sound different because different shells accentuate different frequencies. You don't even need the seashell to hear the noise. You can produce the same "ocean" sound using an empty cup or even by cupping your hand over your ear. Go ahead and try it and vary the distance at which you place the cup near your ear. The level of the sound will vary depending on the angle and distance the cup is from your ear.

最可信的解釋是：這種濤聲似的的聲音其實是聽者周遭環境中的聲響。當你把海螺從耳邊稍稍挪開的時候，海螺捕捉到了背景的聲響，並且在螺內產生了共振。海螺的形狀和尺寸會影響到你聽到的聲音，不同的海螺聽上去會不一樣，因爲它們發生共振的頻率各不相同。其實爲了聽到這種聲響，你用不着專門找一隻海螺來。拿一隻空杯子，或者握一隻空心拳頭貼在耳朵上，你就能造出這種“海的聲音”。快去試試看，也可以試試稍稍調整空杯子離你耳朵的距離，聲音的大小會隨着杯子距離和角度的改變而改變。

Noise from outside the shell also can change the intensity of the sound you hear inside the shell. You can look at the shell as a resonating chamber. When sound from outside enters the shell, it bounces around, thus creating an audible noise. So, the louder the environment you are in, the louder the ocean-like sound will be.

外界的聲響也會影響到你從海螺裏聽到聲響的強弱，你可以把螺體看做一個共鳴腔，外界的聲波傳到螺內之後會在裏面來回反彈，從而形成了聽得見的聲響。所以越是在聲響大的環境裏，“海浪”的聲音也越清晰。