How to remove both axis from a Google Bar Chart (aka Chart API)

Question

I can't find in the Chart API the way to remove any axis from a bar chart. For instance:

cht=bvg
chs=410x150
chd=s:StackOverflow

How to remove the gray x and y axis?

Answer 1

Please try appending

&chxt=x,y&chxs=0,000000,10,0,,000000|1,000000,10,0,,000000&chxl=0:||1:|

Answer 2

All I found is this trick: cover them with a white line and it works

cht=bvg
chs=410x150
chd=s:StackOverflow
chm=r,FFFFFF,0,-0.01,0.01,1
    R,FFFFFF,0,-0.01,0.01,1

...but any "cleaner" way?