ploting only horizontal grids

[Dr Sudheer Joseph <sjo@xxxxxxxxxxxxx>]

Dear Users,
                    Is there any way to put only horizontal grid lines in a 
ferret plot? go graticule will put both on x and y axis. I would like to plot 
the monthly wind direction varying  from 0to 360 digrees  (y axis) and months 
on x axis . I would like to draw horizontal gridlines at  90 ,180, 270, 360 
etc. with out affectino the labeling of x axis.
Please help if any one has a solution 
thank you,
sudheer 
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Dr. Sudheer Joseph         
Scientist-B
Indian National Centre for Ocean Information Services
Plot#3, Nandagiri Hills Layout, Jubilee Hills
Hyderabad, India Pin:500 033
PHONE:+91 040 23553542(O)23044600(R)
Fax:+91 040 23551096
E-mail:sjo@incois.gov.in;sjo@rediffmail.com
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