THE new aluminized mirrors have been acclaimed as most satisfactory by several who have had the job done. A dozen have asked us for "complete instructions' for doing this job themselves. The February number of Publications of the Astronomical Society of the Pacific contains the data, by Professor John Strong of the California Institute of Technology-the man who made the process what it is today. "The data," we say, but the published data do not include the six months of grief involved in teaching the temperamental apparatus to perform-the "period of adjustment," a term usually applied to the first year of marriage and as aptly applied here.

The Bureau of Standards has recently prepared data on another cantankerous job -casting speculum metal. 'Tis said by some that here, too, the correct procedure is to read all about it and then not try it.

Now that winter is approaching-in the antipodes--we suppose somebody in Admiral Byrd's expedition will be making a telescope in the long Antarctic night. We have never learned who. Just before sailing, Admiral Byrd requested a copy of A.T.M., and got it. Who the TN in his party is, we can't say. Has any reader a notion ?

OUR mention the photo-electric guiding in the February number brought out the fact that the idea had already been worked on by not a few. Noël Deisch, 908 G St., N. W., Washington, D. C., states that an article on the same subject appeared in Zeitschriften für Instrumentenkunde, November, 1929, and in Revue d'Optique for December, 1931; while Samuel Wein, 2065 Croston Avenue, New York, cites a paper in Physikalische Zeitung 1905 (p. 838), and states that he wishes to co-operate in this problem with interested workers. We have known for almost a year about the research of one worker on this apparatus but he wishes us to keep his results under our hat until his equipment is entirely freed from bugs-which it is said to be now, or relatively so.

WE have been flirting with the idea of starting a new magazine-a small one of course, at least at first-for the amateur telescope maker, and sent out 480 feelers to that many purchasers of A.T.M. selected at random, enclosing in each case a self-addressed stamped reply card. Of the 480 cards, 185 have come back, and of these 167 are favorable to the idea of organizing a society for amateur astronomers and telescope makers and publishing an organ. On the basis of this we either shall or shall not undertake it! (Tell you later.) The names suggested for the society and for the magazine range from the sublime to something else. The most pleasing return came from that staunch old telescope and spectrohelioscope maker, Henry B. Prescott of Wells River, Vermont, who enclosed two one dollar bills, making him potential subscriber No. 1, and said "Let' go." We have already spent his two dollar (embezzled it) so it looks as if we were morally obligated to start the magazine (By the way please don't emulate Prescott -just yet-for we lack a technically correct way to dispose pro tem of such two dollar bills.) Our tentative idea is a format like that of the Readers Digest, but a thinner magazine, of course, for it takes year to build up a magazine to an armful, an this just happens to have exactly the dimensions of A.T.M. Accordingly-why not make the magazine uniform typographically with A.T.M. and, as it would contain all the advances, regard its bound volumes in the light of new editions of A.T.M.?

A DECIDEDLY neat and inventorish rig for a telescope is that of George Meyers, 106 Ann St., Hartford, Conn. The pictures almost explain themselves. The eyepiece may be turned to any position and locked there by means of the large knurled ring. This is the best solution of a bothersome problem we have ever seen. Meyers' mirror cell is equally ideal, permitting micro-adjustment without loss of alinement. It is like the one shown in A.T.M. page 449, which also screws in.

The three remaining telescopes shown are similar in appearance-two of them in principle. The first is by William Callum, secretary of the Amateur Telescope Makers of Chicago, and he states that it is a copy of Eliason's, shown on page 386 of A.T.M. It has an 8-inch aluminized mirror of f/8.25. The base is of steel, the tube of aluminum. The declination slow motion, on the side, is a new idea and is within reach. It consists of an arm which clamps to the trunnion supports, and which is controlled by a wheel running on a bent threaded rod. It can be set to 10 minutes of arc. Callum says the Chicago group has 53 members and that they are "as enthusiastic a bunch of nuts as you will meet anywhere outside of certain institutions which we will not mention." However, a good recipe for longevity is to get nutty over some hobby and remain so.

Gerald E. McCord of Oak Park, Illinois, a member of the A.T.M.s of Chicago, uses the Porter roller mounting, as Callum and others have. He, wisely we think, likes a wooden tube. Note picture. Such tubes give ]ess trouble from differences of temperature than metal ones.

THE Rev. Cyril E. Martin of the United Church Manse at Preeceville, Saskatchewan, writes:

"I was making my usual round of pastoral calls," he writes, "when I happened upon a copy of the SCIENTIFIC AMERICAN, and there learned that it was possible for even a 'sky pilot' to build his own astronomical telescope. I resolved to try my hand at telescope making. An order for material was sent, a copy of 'Amateur Telescope Making' was obtained and work was begun.

"I had almost completed the polishing process of the mirror when I cracked it while warming it in making a lap. Work was held up for another month while another disk was sent for. This time I had better luck, the mirror was parabolized, set in its cell, and ready for my first view of the moon. I shall never forget that night. While the neighbors were sleeping I was aiming my six-inch at the moon. With trembling hands I adjusted the eyepiece, and that which was first a globe of light started to define itself until the craters and the mountains stood out clearly. Next day the mirror was silvered and next night the neighbors gathered from far and near to look at the moon for the first time through a telescope.

"The polar axis is a piece of 3-1/2 inch shafting which revolves in two six-inch ball bearings. To this shaft is attached a wheel 24 inches in diameter. A worm gear is cut in the edge-this was done in a lathe with only a 9-inch swing, by placing a tap in the chuck and bringing the edge of the wheel against the tap, so that threads were cut. The hour circle markings were made on an aluminum strip and bolted around the edge of the wheel. To the wheel is bolted and braced the fork in which the telescope is swung. You will also note the two Ford brake drums through which the trunnion passes. Between these two drums is a disk of leather which serves as a clamp to hold the tube in declination, when the wheel, which can also be seen, is turned. The whole thing gives excellent results.

"The clock was made from an old Edison cylinder phonograph motor, the spring being replaced by a weight. This will keep an object in the field of the eyepiece for about half an hour."

The Society for Amateur Scientists (SAS) is a nonprofit research and educational organization dedicated to helping people enrich their lives by following their passion to take part in scientific adventures of all kinds.