This preparation..is a sort of cake, roll or ball..made of chopped liver and lights, mixed with gravy, and wrapped in pieces of pig's caul. 1851 MAYHEW Lond. Labour II. (London)

A navigable channel between rocks, sandbanks, etc., in a river or other body of water; a course or path regularly followed by vessels on the sea or in entering and leaving a harbour [OED]

an emphatic expression of approval: Excellent, grand, magnificent, splendid, 'capital'  [OED].

Probably aristocrats. The OED gives a 1797 usage "A parcel of nonsense about jukes and lords, and them sort of fandangus trumpery".

A coin worth one quarter of a penny.

In later Greek and Roman mythology, the three goddesses supposed to determine the course of human life. [OED]

Probably Thomas Maguire (1792–1847), Roman Catholic priest, polemicist, and Irish patriot, [Oxford Dict. Nat.Biog] 

The personification of the river Thames [CPB]

6 feet, a little over 1.8 metres

Favourite was built in 1817. It was owned by Gravesend Steam Packet Company 1817 to 1819 and by the Margate Steam Packet Company from 1820 to c1828 (i). 
In 1829, Favourite seems to have been moved to run between Lincoln and Boston and is depicted on this poster.(ii)

Poster for the Favorite Paddle Steamer, August 1828 

(i) Dix, F Royal River Highway, A history of the passenger boats and services on the river Thames. p 239.
(ii) https://en.wikipedia.org/wiki/William_Pool_(engineer)  

Gratuities; tips.

A dealer in skins or hides of animals [OED]

Commit suicide (One who ‘deliberately puts an end to his own existence, or commits any unlawful malicious act, the consequence of which is his own death’ oed).

Condition, state or trim.

An exclamation expressing, in early use, disgust or indignant reproach. Sometimes more fully fie, for shame! [OED]

Guiseppe Marco Feischi (1790-1836) led an attempt on the life of the King of France in 1835.

Legendary Scottish warrior subject of a long narrative poem recounting his heroic deeds apocryphaly attributed to Ossian.
[www.britannica.com/topic/Ossian - accessed 07Oct2019]

Fireman: person who used to check bits for gas and in some cases fire pockets of it.

Reference:
Palmer, Roy. Ed Poverty Knock: A picture of industrial life in the 19th century through songs ballads and contemporary accounts (Cambridge, Cambridge University Press, 1974) p48

To be the first person to enter the home of (a family member, friend, neighbour, etc.) on New Year's Day. [OED]

Perhaps fag here means , a junior who performs certain duties for a senior as in In English public school usage.