The ancient Phoenicians had an alphabet without vowels. It had 22 consonants, and these consonants were able to handle any word in the vocabulary. The Greeks borrowed from this alphabet, and then they gave it to the Romans, who in turn gave it to us. The moral of the story? Vowels contributed a great big nothing to modern writing.
You depend upon all-consonant words for some of your most important expressions and exclamations, from "hmm" to "shh" to "psst." There are other important all-consonant words, as well. In the list below, be sure to note the examples from great literature!