Location: Optics Lab
A natural thing to attempt is to perform the operations in order by time:
| ABCDEFG | ||
| Sep 6, 1752, 11:20 AM | Caesar shift forwards by 8. | IJKLMNO |
| Apr 19, 1769, 3:15 PM | For any letter which is also in the word JOUSTING, replace it with the corresponding letter in HANDGRIP. | RHKLMIA |
| Feb 29, 1800, 2:30 PM | Replace the third letter with C. | RHCLMIA |
| Jan 17, 1875, 1:11 PM | Caesar shift forwards by 15. | GWRABXP |
| Oct 12, 1920, 1:09 AM | Swap the fourth and fifth letters. | GWRBAXP |
| Apr 26, 1970, 2:32 AM | Replace the last three letters with OWN. | GWRBOWN |
| Aug 3, 1975, 9:04 PM | Caesar shift the second letter backwards by 8. | GORBOWN |
| Aug 3, 1975, 9:05 PM | Rotate left by one letter (that is, move the first letter to the end). | ORBOWNG |
| Oct 25, 1992, 1:13 AM | Swap the first two letters; then rotate left by two. | BOWNGRO |
| Oct 25, 1992, 1:49 AM | Replace the first letter with a copy of the fourth letter. | NOWNGRO |
| Jul 17, 2025, 3:22 AM | Swap the fourth and fifth letters with the sixth and seventh letters. | NOWRONG |
Unfortunately, the phrase NO WRONG only indicates that this was not correct.
We observe, however, that:
- Sep 6, 1752 did not exist. In the switch to the Gregorian calendar, Sep 2 was followed by Sep 14.
- Feb 29, 1800 did not exist. There is no leap day in years which are multiples of 100 (unless they are multiple of 400 - which 1800 is not).
- Apr 26, 1970, 2:32 AM did not exist. During the switch to DST, the hour from 2 AM to 3 AM is skipped.
- Oct 25, 1992, 1:13 AM and 1:49 AM each exist twice. During the switch from DST, 3 AM jumps back to 2 AM, so that hour occurs twice.
If you wait starting at 1700, doing the instruction at the appropriate time, you will skip the 1752, 1800, and 1970 steps, but you will execute both 1992 steps twice. Furthermore, you will not execute the 2025 step by the time you need to call in an answer in 2015.
| ABCDEFG | |||
| Sep 6, 1752, 11:20 AM | Caesar shift forwards by 8. | (Skip) | |
| Apr 19, 1769, 3:15 PM | For any letter which is also in the word JOUSTING, replace it with the corresponding letter in HANDGRIP. | ABCDEFP | |
| Feb 29, 1800, 2:30 PM | Replace the third letter with C. | (Skip) | |
| Jan 17, 1875, 1:11 PM | Caesar shift forwards by 15. | PQRSTUE | |
| Oct 12, 1920, 1:09 AM | Swap the fourth and fifth letters. | PQRTSUE | |
| Apr 26, 1970, 2:32 AM | Replace the last three letters with OWN. | (Skip) | |
| Aug 3, 1975, 9:04 PM | Caesar shift the second letter backwards by 8. | PIRTSUE | |
| Aug 3, 1975, 9:05 PM | Rotate left by one letter (that is, move the first letter to the end). | IRTSUEP | |
| Oct 25, 1992, 1:13 AM | Swap the first two letters; then rotate left by two. | TSUEPRI | |
| Oct 25, 1992, 1:49 AM | Replace the first letter with a copy of the fourth letter. | ESUEPRI | |
| Oct 25, 1992, 1:13 AM | Swap the first two letters; then rotate left by two. | (Execute a second time) | UEPRISE |
| Oct 25, 1992, 1:49 AM | Replace the first letter with a copy of the fourth letter. | (Execute a second time) | REPRISE |
| Jul 17, 2025, 3:22 AM | Swap the fourth and fifth letters with the sixth and seventh letters. | (Skip) |
Hence the answer is REPRISE.