It was and wasn't. Those were the telecoms, transport, and infrastructure companies of their day. They connected the industrial and agricultural output of the

It was and wasn't. Those were the telecoms, transport, and infrastructure companies of their day. They connected the industrial and agricultural output of the United States in much the way Apple, Amazon, Boeing, Verizon, and Walmart (all current components of the DJIA) do today. That said, yes, it's interesting to watch how the components and industrial sectors represented change over time. The first DJIA proper (26 May 1896) featured cotton oil, sugar, tobacco, gas & coke (coal), cattle feed, electrical utility, lead, railroads, leather, rubber, and a holding company (trust) largely engaged in utilities and transportation, and dropped later the same year, along with US Rubber. Changes to the average have been a consistent feature to its origins. Think of those which aren't directly comparable to modern concerns (e.g., oil & gas, electric utilities) as raw materials (mining and ag), transport and logistics, and food (or feed).