What is a telescope or instrument for viewing the sun without injury to the eyes, as through colored glasses, or with mirrors which reflect but a small portion of light. -- He`li*o*scop`ic, a called?

helioscope — A telescope or instrument for viewing the sun without injury to the eyes, as through colored glasses, or with mirrors which reflect but a small portion of light. -- He`li*o*scop`ic, a. (Webster's 1913.)

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