Montesquieu

The Arabs had great wealth : they derei­ved it from their seas and their forests ; and as they pur­cha­sed lit­tle and sold much, they attrac­ted to them­sel­ves the gold and sil­ver of their neigh­bors. Augustus lear­ned of their opu­lence, and resol­ved they should be his friends or his ene­mies.1 He sent Elius Gallus from Egypt to Arabia. He found peo­ple who were idle, tran­quil, and unsea­so­ned. He deli­ve­red bat­tles, set sie­ges, and lost only seven sol­diers ; but the per­fidy of his gui­des, the mar­ches, the cli­mate, hun­ger, thirst, disea­ses, and ill-taken mea­su­res cost him his army.

He the­re­fore had to be content with tra­ding with the Arabs as other peo­ples had done, in other words, brin­ging them gold and sil­ver for their com­mo­di­ties. We still trade with them in the same way : the cara­van from Alep and the royal ves­sel from Suez carry immense sums there.2

Nature had des­ti­ned the Arabs for trade ; she had not des­ti­ned them for war ; but when these tran­quil peo­ples found them­sel­ves on the bor­ders of the Parthians and Romans, they became auxi­lia­ries of both. Elius Gallius had found them to be tra­ders ; Mohammed found them to be war­riors : he gave them some enthu­siasm, and made conque­rors of them.

Ibid.

The caravans from Alep and Suez bring two millions of our money there, and as much again passes fraudulently ; the royal vessel from Suez also brings two million.