Show time of day on Google annotated time line chart
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I am trying to use the Google charts api to create line charts that have datetimes on the x axis and values on the other. Generally these will only be for a 48 hour period, so I really need to show the times of day on the x axis as well as the days. 

Does anyone know how to achieve this please?

Alternatively can anyone suggest another Javascript chart api that would allow this please?