How To Convert From Ntext To Float?

Hello,

I would like to convert a field from ntext field found in one database
table to float field found in another database table. The reason why I
want to do this is a long one.

I have tried the following and playing around with the following:

declare @valuePointer varbinary(16)

<Row cursor logic to initialize @valuePointer to be a pointer to the
source ntext field>

update TargetFloatTable set TargetFloatTable.TargetFloatValue =
CAST(CAST(@valuePointer AS nvarchar) AS float)
where TargetFloatTable.Id = @Id

but is not working for me.

Hoping someone out there can help.

Thanks,

Cally