:w:Hiram Percy Maxim, QST (1916)
“ Of all instruments and devices used in radio work, the audion bulb is by far the most difficult to learn how to handle. Probably 90% of the amateurs of the country do not know how to get the best results from an audion bulb nor how to keep the bulb in best working condition. The information given in Mr. Cole's article is the first time that all of the latest details known about the audion have been put together in one article in such form that the amateur can understand it. ”
