I've been reading an excellent book, With the End in Mind: Dying, Death and Wisdom in an Age of Denial, by Kathryn Mannix.
I wholeheartedly recommend it provided you don't mind some memorably graphic descriptions of death that are likely to linger in your memory.
In particular I love her description of natural death as progressing over years, energy declining and need for rest and sleep increasing, until sleep gives way to unconsciousness and then to death.
This put me in mind of the natural life of an oak tree, which takes 300 years to grow, then rests for 300 years, then takes 300 years to die. It occurred to me there is a correlation with human longevity here. A human who lives into old age without being overtaken by a fatal disease, might expect to live to be ninety years old. Perhaps, like the oak tree (losing a nought for the corresponding human life span) they might grow and mature for 30 years, then maintain a level of vigour for another 30 years, then begin a 30-year decline to death. So death would begin at 60, but not be completed until 90. That makes sense to me.
I have seen numerous well-managed deaths (and a handful of markedly less well-managed deaths), but the most natural deaths I've had the chance to observe have been in animals.
In particular I remember the last year of our dog Mary, who lived to a good age. On her last summer we took her camping with us as usual. I'd noticed that in recent months she seemed especially content, but keen to really savour life, stopping for every interesting smell on her walks, enjoying being out in the garden. Granddad was a Boys Brigade officer and though all our children were girls, we used to go with the BB to their camp every year. That year I was struck by how happily Mary entered into it, more than usual, making me conclude that a dog could have a holiday as much as a human. She loved that time away in the countryside.
On our return, I and my husband and children had to go away again, this time to a big Christian conference where we would be so highly participative that it seemed unwise to take Mary along (we were again under canvas, this time on a huge site, and the events were not appropriate for her). So she stayed with my husband's parents. She and my father-in-law Norman really loved each other.
On our return home, it was instantly apparent that she should not be moved again. She had been slowing down for some time, and was now spending her time just sleeping on a blanket in the sunny warmth of the conservatory. So we didn't make her get up and get into the car, we just let her stay there through that week, dozing.
At the end of her life, Norman was with her. He bent down to stroke her, and she lifted her head to greet him, wagged her tail, and that was the end.
In my own life, now I am in my 60s, I am noticing the downturn of strength and energy. It's come quicker and more insistently than I imagined from what I've known others say. I still have the drive and commitment to see through what I really care about and believe in, but I have to husband my strength judiciously; I can no longer cope with draining relationships or high-stress situations and longer walks are tiring now. I can't multi-task any more (I used to be able to run a large household and write a novel; I don't think I could do either now — certainly not both). I can no longer eat just anything, as I once could — I quickly get significantly ill if I stray from the path of good nutrition. For instance, if I had a sandwich today and a pizza tomorrow I'd enjoy them but it would take me about three weeks to get better; and I can drink tea (I love tea) provided I don't mind the tearing gut pains that follow, along with the swollen tongue and ankles so full of fluid it's hard to walk upstairs! The old girl ain't what she used to be, but if I live and eat carefully I am really very well.
It is the beginning of dying, that may continue its leisurely pace for as much as 30 years if no specific disease process accelerates it in the meantime. It's interesting and peaceful and it doesn't trouble me. I have no fear of death, but I feel the importance of preparing well and of supporting my body systems appropriately. Complementary therapies, inner healing, herbal remedies, essential oils and naturopathic pathways have all proved valuable for the various health problems I've encountered.
My fervent prayer is to keep my hair, teeth, continence, hearing, eyesight, mental faculties (such as they are) and self-possession to the end, to live with an absolute minimum of medical interference, and to die quietly, unexceptionally and alone when the time comes, leaving nothing untidy or distressing for anyone to find; a quick, neat, unheralded and unremarked death, in my own room. That's what I'd like. And I don't mind when it is. Ha ha, in your dreams, you may think — but actually I've known quite a few old people who lived and died that way. So I have high (and determined) hopes.