In Act 1, Scene 1 of The Merchant of Venice, please explain:
" My wind, cooling my broth,
Would blows me to an ague, when i thought
What harm a wind too great at sea might do
I should not see the sandy hour-glass run,
But I should think of shallows and of flats;
And see my wealthy Andrew dock'd in sand,
Vailing her high-top lower than her ribs
To kiss her burial. Should I go to church,
And see the holy edifice of stone,
And not bethink me straight of dangerous
Which touching but my gentle vessel's side,
Would scatter all her spices on the stream,
Enrobe the roaring waters with my silks,
And, in a word, but even now worth this,
And now worth nothing? Shall i have the
To think on this, and shall i lack the thought
That such a thing bechanced would make
But tell not me: I know Antonio
Is sad to think upon his merchandise. "
The Merchant of Venice opens with a very sad Antonio, himself a merchant with much store in his ships that carry valuable merchandise and where all Antonio's wealth lies. This scene foreshadows what the audience begins to suspect - that Antonio's ships will not make it to land - and thus the development of the plot is immediate as this will cause him to be called upon by Shylock to honor a bond of "a pound of flesh" that he will willingly sacrifice on behalf of his dear friend Bassanio.
In the meantime, Antonio has no idea why he is so sad and he admits that "I have much ado to know myself" (I.i.7). Salerio offers his own explanation of the reasons (in this text) and admits that, if he were in Antonio's position "My wind...would blow me to an ague" (24), meaning he would feel ill. He would not be able to patiently wait - as the "sandy hour glass run" - but would spend his time worrying about the shallow water and his "wealthy Andrew dock'd in sand." Antonio's ship is called the Andrew and Salerio would think of the possibilities of it running aground and even turning on it's side in the sand - "vauling her high-top lower than her ribs." His ship would then be doomed as she sinks "to kiss her burial."
Salerio admits that even the distraction of attending church would not help as, as soon as he sees the "holy edifice of stone" he would think only of the rocks against which his ship might become caught thereby scattering "all her spices on the stream." It would be as it the silks on board would "enrobe (the) waters" as they spill into the ocean and from being a wealthy merchant one moment, he would be reduced in an instant and "worth nothing."
This is surely enough to make anyone sad, to consider the possibilities and "think on this." Salerio has then convinced himself - "but tell me not" - and is certain that it is this that makes Antonio "sad to think upon his merchandise."