I had a farm in Africa, at the foot of the Ngong Hills. (1.1.1)
This pretty much tells us all we need to know about Out of Africa. The past tense "had" lets us know that this all remains in the past, and what we will read about the farm are memories, a wish to go back in time.
I remember well the fist time that he ever looked at me and spoke to me of his own accord. (1.2.13)
We're still way early in Out of Africa, just getting to know the narrator, and we might not be too sure how trustworthy she is. That's why declarations like these are important; she insists that she remembers "well" such small details as the first time a kid looked at her, which might convince us that she remembers everything she's writing about well, too.
One year the long rains failed. That is a terrible, tremendous experience, and the farmer who has lived through it, will never forget it. Years afterwards, away from Africa, in the wet climate of a Northern country, he will start up at night, at the sound of a sudden shower of rain, and cry, "At last, at last." (1.3.1-2)
The whole book is about memories, right? That's why it's called a memoir. So the idea that the things that you can't forget are the most terrifying ones you live through kind of sets the tone for the painful memories that are about to get rehashed before our eyes.
"I was not forget you Memsahib. Honoured Memsahib." (1.4.63)
The quote from Kamante's letter is a little cryptic, but it gives us more insight into the importance of memory for the Baroness. She (Memsahib) is honored that her old servant does not forget her. It is really super important for her that she has some connection still with Africa, even though it's all in the past now.
Berkeley, if he had had his small head enriched with a wig of long silky curls, could have walked in and out of the Court of King Charles II. (3.7.4)
Berkeley Cole, the Baroness' good friend, is described as being from another time period. To be exact, the Court of King Charles II, who ruled from 1660 to 1685. The Baroness thinks that Berkeley hung the moon, so this relationship with the past must be a compliment coming from her. That might indicate that she's just a tad nostalgic.
While we were lunching, a party of Masai warriors appeared on the horizon, and approached quickly. [...] They stuck their heads together and began to talk to one another about the aeroplane and us. A generation ago they would have been fatal to us to meet. (3.8.51)
The group of Masai warriors is, in a way, stuck in the past, especially when they are contrasted to the airplane. Sorry, but spears just doesn't cut it against modern machinery. But the narrator knows her history, and knows that if they were in the past, the Masai would have wiped the floor with her. What a difference a few years makes.
Infandum, Regina, jubes renovare dolorem. Troy in flames, seven years of exile, thirteen good ships lost. What is to come out of it? (4.1.20)
Say what? That first part's Latin, from the famous epic poem the Aeneid by Virgil, which tells the story of Aeneas, the founding father of the Romans. Anyway, translation: Great Queen, what you command me to relate, renews the sad remembrance of our fate. It's when Queen Dido makes Aeneas tell her about the fall of Troy, a memory that is painful for him to recall. The Baroness identifies with that past-induced pain.
Whenever I was ill in Africa, or much worried, I suffered from a special kind of compulsive idea. It seemed to me then that all my surroundings were in danger or distress, and that in the midst of this disaster I myself was somehow on the wrong side, and therefore was regarded with distrust and fear by everybody.
This nightmare was in reality a reminiscence of the time of the war. (5.3.27)
It is interesting that the memory, or reminiscence, of World War I, which was pretty rough for the Baroness because she was always either being accused of being a German sympathizer or threatened with the possibility of being sent to a ladies' concentration camp for her own protection, would come back when she is sick or worried. The past is like a latent disease that rears its ugly head when her defenses are low.
I lay in bed and thought of the events of the last months, I tried to understand what it really was that had happened. It seemed to me that I must have, in some way, got out of the normal course of human existence, into a maelstrom where I ought never to have been. (5.4.19)
For the Baroness, looking back into the past, into her memory, is confusing and painful. She's faced with the deaths of loved ones and the loss of her home, but the present doesn't seem to have any connection with the past. In a way, the very book we're reading might be her way of going back and trying "to understand what it really was that had happened."
The outline of the mountain was slowly smoothed and leveled out by the hand of distance. (5.5.29)
In her final farewell to her farm, the Baroness looks back at the Ngong Hills from far away, another train station down the line from Nairobi. From there, the mountains look smooth, as though there were nothing important there. The physical distance between her and the farm is like the time difference between when she writes and what she writes about.