S J Johnson and the limit of 3.25 inch Cooke telescope

 Professor Langley in his ’observations on Mount Etna’ seems to consider the limit for a 3.25 inch aperture at that latitude to be 11.5 magnitude of the Bedford Catalogue and further refers to visibility of iota Orionis with 3.25 inch.

There does not however, appear to be any difficulty in discerning this 11^th magnitude companion of iota Orionis in this country. 

On January 21^st by applying deep magnifiers 260 and 315 to my 3.25 inch Cooke it came into view at once. Lower powers that exhibited the 8.5 magnitude companion did not avail for the more minute point of light.

I find Smyth’s 12^th magnitude star near Aldebaran easily seen with like powers, when the principal was put just outside the field, but not so easy as the distant comes of alpha Lyrae.

Faithfully yours

S J Johnson

Abbenhall Rectory

Gloucester

January 25^th 1881