A transmission study edition
English ↔ Lantern signals
A Dream Within a Dream · sent by signal lamp
Edition: complete · international Morse code sent by light · unreviewed project draft
Before radio, and whenever ships must keep radio silence, messages cross the water as flashes of light: short and long, the dots and dashes of Morse code. The lamp on the right will send you Poe's poem, line by line, the way a signalman would.
Signal lamp
The lamp flashes no faster than two and a half times a second. A short flash is one unit, a long flash three; the light stays dark one unit inside a letter, three between letters and seven between words.
Part one / The poem
The poem, line by line
Every word of Poe's poem in Morse code as a lamp sends it: · a short flash, – a long one. Punctuation is not sent. Select a line number for its study note, or ▶ to watch the lamp send it.
| Line | English · source | Lantern · Morse by light | Send |
|---|---|---|---|
| Take this kiss upon the brow! | – ·– –·– ·TAKE – ···· ·· ···THIS –·– ·· ··· ···KISS ··– ·––· ––– –·UPON – ···· ·THE –··· ·–· ––– ·––BROW | ||
| And, in parting from you now, | ·– –· –··AND ·· –·IN ·––· ·– ·–· – ·· –· ––·PARTING ··–· ·–· ––– ––FROM –·–– ––– ··–YOU –· ––– ·––NOW | ||
| Thus much let me avow — | – ···· ··– ···THUS –– ··– –·–· ····MUCH ·–·· · –LET –– ·ME ·– ···– ––– ·––AVOW | ||
| You are not wrong, who deem | –·–– ––– ··–YOU ·– ·–· ·ARE –· ––– –NOT ·–– ·–· ––– –· ––·WRONG ·–– ···· –––WHO –·· · · ––DEEM | ||
| That my days have been a dream; | – ···· ·– –THAT –– –·––MY –·· ·– –·–– ···DAYS ···· ·– ···– ·HAVE –··· · · –·BEEN ·–A –·· ·–· · ·– ––DREAM | ||
| Yet if hope has flown away | –·–– · –YET ·· ··–·IF ···· ––– ·––· ·HOPE ···· ·– ···HAS ··–· ·–·· ––– ·–– –·FLOWN ·– ·–– ·– –·––AWAY | ||
| In a night, or in a day, | ·· –·IN ·–A –· ·· ––· ···· –NIGHT ––– ·–·OR ·· –·IN ·–A –·· ·– –·––DAY | ||
| In a vision, or in none, | ·· –·IN ·–A ···– ·· ··· ·· ––– –·VISION ––– ·–·OR ·· –·IN –· ––– –· ·NONE | ||
| Is it therefore the less gone? | ·· ···IS ·· –IT – ···· · ·–· · ··–· ––– ·–· ·THEREFORE – ···· ·THE ·–·· · ··· ···LESS ––· ––– –· ·GONE | ||
| All that we see or seem | ·– ·–·· ·–··ALL – ···· ·– –THAT ·–– ·WE ··· · ·SEE ––– ·–·OR ··· · · ––SEEM | ||
| Is but a dream within a dream. | ·· ···IS –··· ··– –BUT ·–A –·· ·–· · ·– ––DREAM ·–– ·· – ···· ·· –·WITHIN ·–A –·· ·–· · ·– ––DREAM | ||
| I stand amid the roar | ··I ··· – ·– –· –··STAND ·– –– ·· –··AMID – ···· ·THE ·–· ––– ·– ·–·ROAR | ||
| Of a surf-tormented shore, | ––– ··–·OF ·–A ··· ··– ·–· ··–· – ––– ·–· –– · –· – · –··SURF-TORMENTED ··· ···· ––– ·–· ·SHORE | ||
| And I hold within my hand | ·– –· –··AND ··I ···· ––– ·–·· –··HOLD ·–– ·· – ···· ·· –·WITHIN –– –·––MY ···· ·– –· –··HAND | ||
| Grains of the golden sand — | ––· ·–· ·– ·· –· ···GRAINS ––– ··–·OF – ···· ·THE ––· ––– ·–·· –·· · –·GOLDEN ··· ·– –· –··SAND | ||
| How few! yet how they creep | ···· ––– ·––HOW ··–· · ·––FEW –·–– · –YET ···· ––– ·––HOW – ···· · –·––THEY –·–· ·–· · · ·––·CREEP | ||
| Through my fingers to the deep, | – ···· ·–· ––– ··– ––· ····THROUGH –– –·––MY ··–· ·· –· ––· · ·–· ···FINGERS – –––TO – ···· ·THE –·· · · ·––·DEEP | ||
| While I weep — while I weep! | ·–– ···· ·· ·–·· ·WHILE ··I ·–– · · ·––·WEEP ·–– ···· ·· ·–·· ·WHILE ··I ·–– · · ·––·WEEP | ||
| O God! Can I not grasp | –––O ––· ––– –··GOD –·–· ·– –·CAN ··I –· ––– –NOT ––· ·–· ·– ··· ·––·GRASP | ||
| Them with a tighter clasp? | – ···· · ––THEM ·–– ·· – ····WITH ·–A – ·· ––· ···· – · ·–·TIGHTER –·–· ·–·· ·– ··· ·––·CLASP | ||
| O God! can I not save | –––O ––· ––– –··GOD –·–· ·– –·CAN ··I –· ––– –NOT ··· ·– ···– ·SAVE | ||
| One from the pitiless wave? | ––– –· ·ONE ··–· ·–· ––– ––FROM – ···· ·THE ·––· ·· – ·· ·–·· · ··· ···PITILESS ·–– ·– ···– ·WAVE | ||
| Is all that we see or seem | ·· ···IS ·– ·–·· ·–··ALL – ···· ·– –THAT ·–– ·WE ··· · ·SEE ––– ·–·OR ··· · · ––SEEM | ||
| But a dream within a dream? | –··· ··– –BUT ·–A –·· ·–· · ·– ––DREAM ·–– ·· – ···· ·· –·WITHIN ·–A –·· ·–· · ·– ––DREAM |
Part two / How it works
Twenty-six rhythms of light
Select a letter to see the lamp flash it. The count shows how often the poem uses it.
Short and long
A dot is a short flash of one unit; a dash is three units. Signallers say di and dah, and learn letters by their rhythm, never by counting.
E · T – A ·– N –·
The dark between
The gaps carry as much meaning as the light: one unit inside a letter, three between letters, seven between words.
DREAM: –·· ·–· · ·– ––
Working the lamp
A signalman aims the lamp at the other ship and works a lever or trigger that opens a shutter or tilts a mirror; the bulb itself stays lit.
Reading the lamp
The receiving signaller watches, often through binoculars, and reads the letters off as they come, often calling them aloud to a second sailor who writes them down.
Practice
Read the lamp
The small lamp flashes one letter from the poem. Pick the letter. Flash it again as often as you like.
0 of 0 correct
Practice with every word
Every word of the poem
All 85 different words of the poem in Morse, in the order they first appear. Read the code, watch the lamp, then reveal the word.
How to practise
- Read the code aloud as di and dah: · is di, – is dah.
- Watch the lamp send it, and count nothing; listen to the rhythm.
- Reveal the word, then find it in the poem.
- At night, flash a word with a torch to a friend across the street.
See the full word list (85 words)
| take | – ·– –·– · | line 1 · 1× |
| this | – ···· ·· ··· | line 1 · 1× |
| kiss | –·– ·· ··· ··· | line 1 · 1× |
| upon | ··– ·––· ––– –· | line 1 · 1× |
| the | – ···· · | line 1 · 6× |
| brow | –··· ·–· ––– ·–– | line 1 · 1× |
| and | ·– –· –·· | line 2 · 2× |
| in | ·· –· | line 2 · 5× |
| parting | ·––· ·– ·–· – ·· –· ––· | line 2 · 1× |
| from | ··–· ·–· ––– –– | line 2 · 2× |
| you | –·–– ––– ··– | line 2 · 2× |
| now | –· ––– ·–– | line 2 · 1× |
| thus | – ···· ··– ··· | line 3 · 1× |
| much | –– ··– –·–· ···· | line 3 · 1× |
| let | ·–·· · – | line 3 · 1× |
| me | –– · | line 3 · 1× |
| avow | ·– ···– ––– ·–– | line 3 · 1× |
| are | ·– ·–· · | line 4 · 1× |
| not | –· ––– – | line 4 · 3× |
| wrong | ·–– ·–· ––– –· ––· | line 4 · 1× |
| who | ·–– ···· ––– | line 4 · 1× |
| deem | –·· · · –– | line 4 · 1× |
| that | – ···· ·– – | line 5 · 3× |
| my | –– –·–– | line 5 · 3× |
| days | –·· ·– –·–– ··· | line 5 · 1× |
| have | ···· ·– ···– · | line 5 · 1× |
| been | –··· · · –· | line 5 · 1× |
| a | ·– | line 5 · 10× |
| dream | –·· ·–· · ·– –– | line 5 · 5× |
| yet | –·–– · – | line 6 · 2× |
| if | ·· ··–· | line 6 · 1× |
| hope | ···· ––– ·––· · | line 6 · 1× |
| has | ···· ·– ··· | line 6 · 1× |
| flown | ··–· ·–·· ––– ·–– –· | line 6 · 1× |
| away | ·– ·–– ·– –·–– | line 6 · 1× |
| night | –· ·· ––· ···· – | line 7 · 1× |
| or | ––– ·–· | line 7 · 4× |
| day | –·· ·– –·–– | line 7 · 1× |
| vision | ···– ·· ··· ·· ––– –· | line 8 · 1× |
| none | –· ––– –· · | line 8 · 1× |
| is | ·· ··· | line 9 · 3× |
| it | ·· – | line 9 · 1× |
| therefore | – ···· · ·–· · ··–· ––– ·–· · | line 9 · 1× |
| less | ·–·· · ··· ··· | line 9 · 1× |
| gone | ––· ––– –· · | line 9 · 1× |
| all | ·– ·–·· ·–·· | line 10 · 2× |
| we | ·–– · | line 10 · 2× |
| see | ··· · · | line 10 · 2× |
| seem | ··· · · –– | line 10 · 2× |
| but | –··· ··– – | line 11 · 2× |
| within | ·–– ·· – ···· ·· –· | line 11 · 3× |
| I | ·· | line 12 · 6× |
| stand | ··· – ·– –· –·· | line 12 · 1× |
| amid | ·– –– ·· –·· | line 12 · 1× |
| roar | ·–· ––– ·– ·–· | line 12 · 1× |
| of | ––– ··–· | line 13 · 2× |
| surf-tormented | ··· ··– ·–· ··–· – ––– ·–· –– · –· – · –·· | line 13 · 1× |
| shore | ··· ···· ––– ·–· · | line 13 · 1× |
| hold | ···· ––– ·–·· –·· | line 14 · 1× |
| hand | ···· ·– –· –·· | line 14 · 1× |
| grains | ––· ·–· ·– ·· –· ··· | line 15 · 1× |
| golden | ––· ––– ·–·· –·· · –· | line 15 · 1× |
| sand | ··· ·– –· –·· | line 15 · 1× |
| how | ···· ––– ·–– | line 16 · 2× |
| few | ··–· · ·–– | line 16 · 1× |
| they | – ···· · –·–– | line 16 · 1× |
| creep | –·–· ·–· · · ·––· | line 16 · 1× |
| through | – ···· ·–· ––– ··– ––· ···· | line 17 · 1× |
| fingers | ··–· ·· –· ––· · ·–· ··· | line 17 · 1× |
| to | – ––– | line 17 · 1× |
| deep | –·· · · ·––· | line 17 · 1× |
| while | ·–– ···· ·· ·–·· · | line 18 · 2× |
| weep | ·–– · · ·––· | line 18 · 2× |
| O | ––– | line 19 · 2× |
| God | ––· ––– –·· | line 19 · 2× |
| can | –·–· ·– –· | line 19 · 2× |
| grasp | ––· ·–· ·– ··· ·––· | line 19 · 1× |
| them | – ···· · –– | line 20 · 1× |
| with | ·–– ·· – ···· | line 20 · 1× |
| tighter | – ·· ––· ···· – · ·–· | line 20 · 1× |
| clasp | –·–· ·–·· ·– ··· ·––· | line 20 · 1× |
| save | ··· ·– ···– · | line 21 · 1× |
| one | ––– –· · | line 22 · 1× |
| pitiless | ·––· ·· – ·· ·–·· · ··· ··· | line 22 · 1× |
| wave | ·–– ·– ···– · | line 22 · 1× |
Background
Light across the water
Colomb's lantern
Captain Philip Colomb of the Royal Navy first put flashing dots and dashes from a lantern into practice in 1867. His lamp burned limelight, and his first code was not Morse; Morse was adopted later.
The Aldis lamp
In 1944 Arthur Cyril Webb Aldis patented a small hand-held signal lamp with an improved shutter. His name stuck: many sailors still call any signal lamp an Aldis.
Still in service
Navies use signal lamps when radio must stay silent, and control towers keep light guns to signal aircraft whose radios fail. A good signaller manages about 14 words a minute.
Sources
Pages consulted
- Signal lamp, Wikipedia
- Philip Howard Colomb, Wikipedia
- Visual Signalling, Royal Navy Communications Branch Museum/Library
- US patent 2363566, A. C. W. Aldis, Signaling lamp (1944)
- Morse code, Wikipedia
- Recommendation ITU-R M.1677-1, International Morse code