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Previously: Pharyngeals ח (Heth) and ע (Ayin) 

Now: Interdentals ת (Taw), ש (Shin), ד (Daleth) and ז (Zayin)

Arabic has two distinct letters Taw, a stop <t>, like Hebrew תּ, and a fricative <th>, like Hebrew ת without the dagesh. But in Arabic these two consonants are really distinct consonants, not different pronunciations of the same consonant depending on vowel configuration.

Aramaic, like Hebrew, has only one letter for <t> and <th> and pronunciation is defined by the vowel configuration. The two consonants describe the same phoneme, meaning that they are allophones, meaning that they mean the same thing.

Taw, Shin, Daleth and Zayin also derive from Egyptian hieroglyphs.

Taw derives from the symbol for a mark, Indiana Jones will love this, an X.

The Hebrew word "taw" means "mark" as well, which suggests to me that whoever took the symbol to mean the consonant <t> used it first to write the work for "mark" in both Egyptian and Hebrew (or Canaanite) before using it for all occurences of the consonant the Hebrew "mark" started with.

Arabic Thaw (Taw fricative) also derives from this symbol.

Word correspondences show that an original Semitic <th> turned into <t> in Aramaic and <sh> in Hebrew while remaining <th> in the more conservative dialects of Arabic.

Shin derives from a hieroglyph for a tooth. The word "shin" (spelt with a Shin) also means "tooth" in Hebrew.

This again suggests that the symbol was used first for the Egyptian word for "tooth" and then for the Hebrew word for "tooth" and finally as a symbol for the consonant the word "tooth" started with in Hebrew, <sh>.

Now guess what the symbol for Daleth meaning "door" in Hebrew meant in the ancient Egyptian language?

It was a door. Again the process was from the Egyptian "door" to the Hebrew "door" to the consonant <d>.

Incidentally, this same transformation happened within the Egyptian language as well, but not to the extent as in Hebrew, Phoenician and Aramaic. Egyptians too started using hieroglyphs representing words to represent the starting consonants of the words. (As in Semitic languages, in the Egyptian language it was not terribly necessary to write vowels.)

Many words in Arabic starting with ذ (Daleth fricative) have corresponding words in Hebrew starting with ז (Zayin) and in Aramaic with ד (Daleth stop or fricative depending on vowel configuration). Seeing that Arabic has two distinct Daleths (stop and fricative as distinct consonants) and that the consonant managed to become a <z> in Hebrew and <d> in Aramaic, the logical conclusion is that the original consonant was a <dh>, a fricative of <d>, like "th" in English "this".

Finally, the Zayin derives from no hieroglyph but simply represents first a sword and later the consonant the Hebrew word for sword ("zayin") begins with.

An interesting correspondence is the aforementioned <t> <- <th> -> <sh>. 

Obviously not all <sh> in Hebrew have correspondences to <t> in Aramaic and <th> in Arabic. This is how we can see how the consonants developed. The extinction of the (original*) <th> in Hebrew caused words with <th> to become words with <sh> but this didn't affect words with an original <sh> (for example שיר shir = song) or even words with original <sh> where the <sh> became an <s> in Arabic (שלום shalom = peace, سلام salaam = peace).

*Recall that <t> in Hebrew is pronounced <th> after a vowel, re-creating a sound that had died out in Hebrew before. Apparently the same happened in Aramaic.

And here are a few examples of the Dhalet - Zayin - Dalet range:

Next I will look at the ridiculous amount of non-empathic "s"-like sounds in Hebrew and Arabic.