Beginner's Corner
June, 1939

PROSPECTIVE beginners at telescope making very frequently have attacks of deep-dyed doubt regarding their ability to make a telescope, and to these we commend the two photographs reproduced here, showing telescopes made respectively by an 11-year-old lad and a lady. Not that telescope making is a juvenile or feminine hobby- in most cases it pretty definitely isn't. Simply, these telescope makers are beyond average in ability, for age and sex, but not men.

Donald Bird and his telescope

Donald Bird is the youth and Wallace C. Swank, science teacher at the Eaton Rapids Public Schools. Eaton Rapids, Mich., sends us an account of his success, stating that "Donald was 11 years old when he finished this telescope. Some of your readers may think," he continues, "that Donald did perhaps a little of the work and an older person most of it, but such is not the case; he did it all. His mirror is 4-1/4" in diameter with focal length 34", and is mounted in an octagonal tube of plywood. He used pipe fittings for the mounting. So far as the conductor of this department can recall, Donald Bird is the youngest lad to have made so creditable a telescope. Natural mechanic.

Mrs. Bonelli and her reflector

The lady in the other photograph is Mrs., Albert M. Bonelli, 2515 Drummond St.,Vicksburg, Miss., and she states that "the greatest thrill I've had in years was reading in Scientific American that it wasn't impossible for me to do what others had done, and that I might realize a life's ambition by making and owning a telescope. So I obtained a kit of materials, your instruction book 'Amateur Telescope Making,' and got busy. This 6" reflectorwas the outcome, after 72 total hours of hard work."

In difficulty the amateur telescoptical hobby starts at the level of work such as these examples and may be made to extend just as far as the follower cares to extend it toward and into really advanced work.

FROM a very old hand at the telescope making hobby, Harold A. Lower, of San Diego, we receive the following comment: "Here is something I think you ought to bear down on, in your Beginner's Corner-the chapter in 'Amateur Telescope Making' on zonal testing. I have found that there are a surprising number of amateurs, some of whom have made several mirrors, who don't even know that chapter is in the book. Lots of them think all they need to do is use a Ronchi grating, and polish until they get curved lines. Naturally, the result is usually a deep hyperbola. Honestly, I think there would be more good mirrors if the Ronchi test had never been heard of. It is useful, of course, but most beginners depend on it too much."

The chapter on zonal testing extends from page 96 to page 100 of "ATM".