The wealth gap is provoking much contemporary anxiety. But the financial imbalance between, say, Bill Gates or Warren Buffet and the Big-Mac slinger is a shadow of that which existed between the first American capitalist barons and those at the bottom of the heap. The US was developing like a runaway train, taxes were low, labour laws and financial regulation were almost non-existent and concern for the environment was an alien concept.
The fortunes amassed were truly staggering and few, if any, were bigger than that accumulated by W.A. Clark between 1860 and the 1920s. Today he would be called an entrepreneur. He graduated from buying and selling eggs to miners to owning huge chunks of America's copper reserves, building railroads, running banks and being involved in the founding of Las Vegas.
At the height of his success he built the most costly mansion in New York: a 121-room fantasy so expensive that he won a huge reduction in local tax on the grounds that it was unsaleable. No one else could afford to run it. And he was right. It lasted less than 30 years.
But this extraordinary piece of real estate was only one in the property portfolio of Clark and his heirs. His second wife, Anna, and his daughter, Huguette Clark, continued acquiring residences of breathtaking opulence. One of them, Le Beau Chateau in Connecticut, caught the attention of reporter Bill Dedman who discovered that it had been empty but maintained for over 50 years.
Further investigation revealed Huguette's prime apartments in New York and another unoccupied mansion occupying 9ha of Santa Barbara clifftop in California. This too had been unoccupied for more than 50 years but had been kept in pristine condition.
Dedman had stumbled across a story almost stranger than fiction and with the co-operation of Paul Clark Newell jnr, a member of the family who had researched its remarkable history, he has produced a spellbinding read, told with journalistic panache.
It has every element you would expect in an airport best-seller. There is politics. W.A. Clark was elected - and expelled - from the US Senate for political skulduggery that was scandalous even by the freebooting standards of the late 1800s. There is sex. The patriarch of the clan had a series of unorthodox liaisons before, at the age of 62, he married Anna, who was 23, and there is reason to doubt that formal marriage took place.
There is mystery as Dedman tracks down Huguette, who gradually withdrew from society and became a total recluse, spending the last decades of her life in hospital although she seemed to be in perfect health for her age.
But the unbeatable attraction is the money.
The spending is beyond comprehension. On one occasion Anna pops out, as we might to the ATM and the Warehouse, cashes in a Cezanne and buys four Stradivarius instruments so a musician protege can start a string quartet.
Huguette, a generous soul, makes gifts on a prodigious scale. Her nurse receives largesse of more than US$30 million. The families of craftsmen who work on her beloved dolls' houses are kept for life. But there's plenty left. W.A. divided his estate equally between his five children, but that share still allowed Huguette to leave more than US$300 million to be squabbled over when she died at the age of 104 in 2011. The battle for the loot is a legal quagmire, still sucking in cash like a modern Jarndyce and Jarndyce (see Dickens' Bleak House) and from which few players emerge with any credit.
This is a sensational thriller but it is also a reflection of the nature of extreme wealth and its effects on both those who have it and those who come into contact with it. Huguette Clark seems to have been a gentle soul of vaguely artistic and scholarly interests who did no harm and whose generosity benefited many. Dedman's conclusion, and his case is convincing, is that she lived a life with its own integrity. She could afford it.
Empty Mansions by Bill Dedman and Paul Clark Newell, Jr (Atlantic Books, $39.99).