Chapter 4: 30-41
Epictetus (ca. 55–ca. 135) was a Greek Stoic philosopher who focused more on ethics than the earlier Stoics had. Repeatedly attributing his ideas to Socrates, he held that our aim was to be masters of our own lives. The role of the Stoic teacher, according to Epictetus, was to encourage his students to learn, first of all, the true nature of things, which is invariable, inviolable and valid for all human beings without exceptions. Wikipedia
Some things, said Epictetus, are in our power, others are not. We have no control over how the dice of life are cast; what we do control is the hand we play once they are thrown. The failure to observe this distinction leads to unlimited anxiety. If you try to avoid disease, death and poverty, you will live in misery, because none of them, particularly death, are ever under our control. Happiness can emerge only from attention to those things that we do have command over - our thoughts, actions and reactions. Peace comes from living a simple life in which we have disciplined our own thinking and trimmed our desires and aversions to a minimum.
The quote paraphrased by the Rev'd Cherrycoke comes from the Enchiridion (135 A.C.E.) ("handbook"), in which Epictetus promotes the Stoic philosophy of acceptance. It is believed that Epictetus himself wrote nothing and what remains of his thought was transcribed by his pupil Arrian. The twenty-first point reads:
- "Let death and exile and every other thing which appears dreadful be daily before your eyes; but most of all death: and you will never think of anything mean nor will you desire anything extravagantly." 
death upon the Whir fore and aft
That is, the length of the ship.
A boy employed on warships to carry gunpowder from the magazine to the guns.
the snug Shambles of the Seahorse
Shambles, in this context, likely means abattoir, which is a building where animals are butchered.
A slang term for the human face, from physiognomy which means the face.
The only definition for this word in the OED is an adjective: "Having thumbs; spec. of or relating to the former order Pollicata of mammals having opposable digits, which included monkeys, lower primates, and many marsupials." I'm assuming the narrator is turning it into a verb here, which would seem to indicate that Ethelmer is giving his uncle a "thumbs-up"? 'Superpollicates' comes later and would seem to mean the same.
Can't squeeze blood from a turnip.
The Ramillies-class ships of the line were a class of nine 74-gun third rates, designed for the Royal Navy by Sir Thomas Slade. There were two distinct sub-groups; four ships were built in the Royal Dockyards to the original design, approved on 25 April 1760. The actual HMS Ramillies entry was launched in 1763, suffered damage in a storm in 1782 and was finally abandoned and burned later that year.
Tail of the Bolt / Rame Head
Bolt Tail is a headland in Devon and Rame Head is a headland in southeast Cornwall.
Sixth rate was the designation used by the Royal Navy for small warships mounting between 20 and 24 carriage-mounted guns on a single deck, sometimes with smaller guns on the upper works and sometimes without. It thus encompassed ships with up to 30 guns in all. In the first half of the 18th century the main battery guns were 6-pounders, but by mid-century these were supplanted by 9-pounders. Wiki entry
Sailors holystoning the deck
A holystone is a block of soft sandstone used for scrubbing the wooden decks of a ship, usually with sand and seawater; sometimes called a bible.
A topgallant sail is the square-rigged sail or sails immediately above the topsail or topsails on a square rigged sailing vessel.
A shipmate in charge of preparing gruel.
Now known as Her Majesty's Naval Base (HMNB) Devonport, see Wiki entry.
disaster ... at Quiberon Bay
See Battle of Quiberon Bay. Wikipedia
Originally a French sentinel's challenge, originally meaning "Long live who?" but in its other sense, "Who's alive?", qui vive is used idiomatically as a adjective to mean to be on the alert or vigilant.
A French version of the rural American metaphor hind tit (or teat). The place of lowest status. téton = "tit"; dernier = "last position" or "back row".
Latitudes and Departures
1: 5-11, 2: 12-13, 3: 14-29, 4: 30-41, 5: 42-46, 6: 47-57, 7: 58-76, 8: 77-86, 9: 87-93, 10: 94-104, 11: 105-115, 12: 116-124, 13: 125-145, 14: 146-157, 15: 158-166, 16: 167-174, 17: 175-182, 18: 183-189, 19: 190-198, 20: 199-206, 21: 207-214, 22: 215-227, 23: 228-237, 24: 238-245, 25: 245-253
26: 257-265, 27: 266-274, 28: 275-288, 29: 289-295, 30: 296-301, 31: 302-314, 32: 315-326, 33: 327-340, 34: 341-348, 35: 349-361, 36: 362-370, 37: 371-381, 38: 382-390, 39: 391-398, 40: 399-409, 41: 410-421, 42: 422-435, 43: 436-439, 44: 440-447, 45: 448-451, 46: 452-459, 47: 460-465, 48: 466-475, 49: 476-483, 50: 484-490, 51: 491-498, 52: 499-510, 53: 511-524, 54: 525-541, 55: 542-553, 56: 554-561, 57: 562-569, 58: 570-574, 59: 575-584, 60: 585-596, 61: 597-607, 62: 608-617, 63: 618-622, 64: 623-628, 65: 629-632, 66: 633-645, 67: 646-657, 68: 658-664, 69: 665-677, 70: 678-686, 71: 687-693, 72: 694-705, 73: 706-713