$('#s1').cycle({
    fx:     'fade',
    timeout: 16000,
    delay:  -12000
});

$('#s2').cycle({
    fx:     'fade',
    timeout: 16000,
    delay:  -8000
});

$('#s3').cycle({
    fx:     'fade',
    timeout: 16000,
    delay:  -4000
});

$('#s4').cycle({
    fx:     'fade',
    timeout: 16000
});