A while ago, I translated Menger’s “Kapitaltheorie” into the English language. I’m not sure if these quotes provide an adequate answer to your question, but if nothing else, they will give some insight as to how the Austrian definition of capital differed from mainstream/Smithian views on capital early on.
The doctrine that only those goods that are products may become capital (as long as they are destined to serve in a productive process) is above all contradicting practical experience.
Even those theoreticians that professionally teach said doctrine will hardly reject the notion that in numerous cases, even “sheer natural objects“ may become “capital“ (under the same conditions as “products“). No practitioner in the field of business, not even an unbiased theoretician will negate that – if it is agreed upon that resources devoted to income generation are considered “capital“ – said resources (e.g. logs, fruits, mineral water etc.) are to be called “capital“ even if their physical origins necessarily make them sheer natural objects whose relative scarcity is the only reason for their status as economic goods. For example, who could claim that a naturally grown tree used to build a ship is not capital whereas a purposefully planted, equally constituted tree used for the same purpose is? That natural mineral water is not capital, but that water refined by humans is?
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According to A. Smith, land property does not per se gain the status of capital. This status hinges on the amount of labor or the cost of amelioration employed on it. However, Smith does not draw the analogous conclusion with respect to other objects of nature, especially movable ones. Barring land property (more accurately: immovable goods!) and, as will be pointed out below, human labor, any object of nature becomes a “product“, that is to say “capital“, per se once human labor has been employed on it and as long as it is devoted to further production; land property, on the other hand, is said to become capital only to the extent of the amount of labor and capital used on it while remaining a “natural factor“ all along. A. Smith ex professo rejects the notion that land property may become a product as such, or even, in accordance with its entire market value, capital. Logs produced without labor and cost, naturally grown fruits, effortlessly found gems and other objects of this kind may become “products“ (per se) and “capital“ (in accordance with their market value) if labor or expenditures are spent on them afterwards; land property, however, is said to only become capital to the extent of its ameliorations, regardless of the amount of labor spent on it.
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Products of labor are mostly economic goods and tend to have a market value, yet not because labor or products of labor have been used on them, but because economic actors tend to only use labor or products of labor on such goods that are likely to gain the status of economic goods and a market value. Cause and effect are as confused here as in the claim that the possession of a train ticket is the reason for the desire to travel to the chosen destination.
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Sheer objects of nature, labor unrefined by capital or labor expenditures and “products devoted to further production“ are the primary factors of the physical production of goods and, as a consequence according to Smithian thought, also the primary factors of income generation – the last components into which the annual produce of a nation dissolves.
Thus, his main intention has not been to determine the real meaning of capital, but to classify products devoted to further production as a third source of income (besides sheer factors of nature and labor untouched by capital expenditures) in his theory of income sources, which eventually led him to his capital doctrine. “Capital“ described a scientific category that resulted from a theoretical examination whose aim was to analyze income, a theoretical analysis that primarily concerned itself with fundamentally different problems than the definition of the term “capital“, regardless of whether this scientific category matched the real capital phenomenon or not.