A Rough Calculation of Expences to convey Major Laing & Party to Tombuctoo & the termination of the Niger:
To His Highness before leaving Tripoli: $200
To have untouched on your arrival at Tombuctoo: $3000
A present to Hateeta to conduct you to Twat: $500
Do. to the Sheikh sent by the Bashaw: $500
Hateeta’s Friend at Twat to take you to Tombuctoo: $500
The Moor recommended by Messrs Denham & Clapperton: $150
Governor of Gadames Ghadames: $250
Small expences unforeseen say: $300
To Purchase Camels, Horses, Mules, to arm & clothe camel Drivers, say: $1000
Expences from Tripoli to Tombuctoo, say: $1000
on departure from Godames to the Bashaw: $2000
from Twat: $2000
from Tombuctoo: $4000
N.B. These sums are certainly large but are in my opinion necessary to ensure success to the Mission as well as your personal safety, and every One of the Africans will expect to make a sort of Harvest of your liberality, & by thus purchase their fidelity, it will leave a lasting Impression of a generous & disinterested conduct envinced by the English Nation.
That is from the fun but not at all new The Conquest of the Sahara, by Douglas Porch, and yes I have double checked the spelling. This anecdote is also a lesson in how the British bureaucracy worked.