"Double" consonants

In spite of the different spellings, the length of the [t] sound in "pretty" is not significantly greater than the length of [t] in "city". Another example: "account" vs. "a count". Phoneticians say that all Eng. consonants are short or that length does not produce pairs of words that differ only because of that. One exception might be "holy" vs. "wholly" (short vs. long [l]) but not all speakers of Eng. are aware of that and use the different lengths systematically.

Longer consonants are occasionally found in compound words like "penknife" [nn] or other expressions like "bus stop" [ss].

This premise is relevant because the length of consonants, instead, has a major role in It. But before we go on to that, why "double" between inverted commas? Because there are two letters in writing but not two sounds in speaking - just one longer sound. Phoneticians rightly insist that the correct transcription is not, say, [ss] but [s:], where [:] is the symbol for length.

There are several pairs of It. words where only the length of a consonant makes the difference. Examples: "caro - carro" ( dear - cart), "pala - palla" ( shovel - ball); "vile - ville" ( coward - villas); "Luca - Lucca( Luke - Lucca, a Tuscan city); "casa - cassa" ( house/home - box/case/cash); "pani - panni" ( loaves - clothes)...

In other cases there are other variations that occur together with "doubling". In the following examples, semi-open and semi-closed "o" alternate: "dona - donna" ( he/she donates - woman); "tono - tonno" ( tone - tuna fish)...

Most words containing "double" consonants do not contrast with words with short consonants. "Battere, doppio" ( to beat, double) exist, "*batere, *dopio" don't exist: all the same, the long consonants must sound long, "by the clock".