3i! 



SCIENCE. 



[Vol. XX. No. 513 



Pseudaurora Borealis ; or, What ■wa.s It ? 



The observations which I am about to recount ma.y not be new 

 to others, but, as I have failed to see or hear of any such after 

 several years' waiting, I communicate mine, hoping tliat by doing 

 so I may call them out if there are any. The business portions of 

 Minneapolis, Minn,, had for many years been lighted by the 

 Biush system of electricity, during which time that metliod of 

 street illumination had been extended considerably in all direc- 

 tions, leaving, however, much more that continued to be lighted 

 by gas and oil. I had occasion to visit the suburbs of the city 

 under circumstances which delayed my return until a very late 

 hour, and for a considerable portion of my way the latter method 

 of lighting prevailed. On passing into the electrically-lighted 

 section, my attention was arrested by the appearance of the aurora 

 borealis, or northern lights. 



It being in the month of February, and their appearance at that 

 season by no means a rare event, while the lateness of the hour, 

 and the severity of the cold, with the air so filled with frost as to 

 give an appearance of a light fog, I was hastening forward as 

 rapidly as I could on foot, when I noticed that the aurora had 

 disappeared, but after a few steps more it reappeared. Pausing a 

 moment, I saw there was no mistaking the fact of my seeing a 

 genume display of northern lights, I again went forward with the 

 same experience of interruption. This circumstance awakened a 

 suspicion that the phenomena were in some way to be accounted 

 for by the presence of the electric lights, and, after another brief 

 pause to make myself assured of the certainty of my observations, 

 I went back along the way I had come until fully out of the zone 

 of the Brush lights, and well into that of the gas-lamps, where I 

 found no signs of an aurora. 



Returning slowly towards and into the former illumination, all 

 of the observations were repeated precisely as at first, until having 

 passed a given burner, when the phenomena again ceased. After 

 repeatedly changing my position in relation to a special burner in 

 a northern and southern direction, during which I discovered that 

 the phenomena was most distinct when I was observing them at 

 or about the angle of 60° to the burner, a corresponding move- 

 ment east and veest gave no more facts, and after once more noting 

 the characteristic movements of the serrated columns of partially 

 prismatic radiations of the auroral beams along the penumhrated 

 arc, I went on my way resolved to keep a good outlook for another 

 such observation, but it has never come after nearly fivp years 

 of waiting. If others have noticed the same, or similar phenomena, 

 it will be gratifying, and in order, for them to say so. 



P. L. Natch, M.D. 



Anacortes, Washington, Nov. 3. 



few instances I have seen humming-birds perch upon the bark 

 below the holes in order to drink long without being forced to 

 keep their wings moving while enjoying the sweet sap. 



In some cases I have placed small birch-bark cups upon trees 

 frequented by the sap-suckers and their guests, and in each such 

 instance the humming-birds have been as quick as the wood- 

 peckers to discover the diluted maple syrup with which the cups 

 were filled, and to drink it in considerable quantities. I remem- 

 ber seeing one drink for sixty seconds, with a ten seconds' rest in 

 the middle of the minute. 



Most of the " orchards" at which I have seen humming-birds 

 as visitors from year to year have been composed of red maples 

 or gray birches. At one of the birch orchards I shot two hum- 

 ming-birds, a male and a female, in order to ascertain whether 

 more of their kind were visiting the holes. Only nine minutes 

 elapsed before another was at the holes drinking. 



Feank Bolles. 



Cambridge, Nov. 28. 



Sense of Direction. 



Some time in the fifties, in Oregon, a party of prospectors took 

 a mule team, wagon, and camping equipage on a prospecting 

 tour. In order to be correct in their local geography, and to re- 

 trace their steps should they find anything worthy of a re-visit, 

 they took a civil engineer along, who took the bearing of every 

 course and the distance was chained. 



When they gave up the prospecting enterprise, their route had 

 been so tortuous that they decided to take the direct route for the 

 home camp. The engineer footed up the latitudes and departures 

 of the courses run, and made a calculation of the course home, 

 and all struck for the home camp. When they reached the end 

 of their course, night had overtaken them, and they found them- 

 selves, not in the home camp, but in the woods, with no objects 

 or land-marks that any of the party could recognize. 



As the engineer took no " back-sights," or check bearings, he 

 said that local attraction somewhere in their journey had thrown 

 him off a little and that they were in the neighborhood of the 

 home camp. At this, the driver turned one of his mules loose, 

 which went directly to the camp, about three-quarters of a mile 

 distant. As the mules were not allowed to run at large, for fear 

 of wandering off or being stolen by Indians, this mule had never 

 before been over that route, and must have had a sense of direc- 

 tion. It was a joke on the engineer which he did not relish, 

 thougli it had great -'staying qualities" 



John T. Campbell. 



Bockvllle, Ind., Nov. 14. 



The Humming-Bird's Food. 



For three years I have made a special study of the habits of the 

 yellow-bellied, or sap-sucking woodpecker {Sphyrapicus varius), 

 as found in the White Mountains of New Hampshire. The birds 

 arrive in that region near the middle or 30th of April, and remain 

 until about the middle of October. During the whole of this period 

 they derive the more important part of their food-supply from 

 sap-yielding holes which they drill through the bark of red maples, 

 red oaks, poplars, white and gray birches, the white ash and some 

 other trees and shrubs. In every instance where I have found a 

 well-marked drinking-place established by the sap-suckers, hum- 

 ming-birds have been regular attendants upon it during the sum- 

 mer months. 



I have paid hundreds of visits to these "orchards" of the sap- 

 suckers, and have watched them for many hours at a time. By 

 so doing I have ascertained that, as a rule, one individual hum- 

 ming-bird seems to acquire a sort of easement in the sap-fountains 

 of the woodpeckers, and if another ruby-throat attempts to drink 

 sap at his spring, violent resistance is offered. 



The humming birds, at "orchards" where they are not molested 

 by the woodpeckers, drink scores of times in the course of the 

 long summer day. When not drinking they are usually perched 

 OD twigs a few yards from the holes, keeping their nervous heads 

 wagging from side to side while watching for intruders. In a 



Electrical Phenomena on the Mountains of Colorado. 



In Science for Sept. 23, Mr. O. C. Chariton describes a moun- 

 tain experience, and inquires if it is common or dangerous. 



The peculiar buzzing and crackling sound, the standing of the 

 hair on end, etc.. are extremely common on the mountains of 

 Colorado. The prospectors, miners, and drivers of pack trains to 

 the high mines (above 11,000 feet) live in the midst of these 

 electrical phenomena, and often find much amusement in observ- 

 ing their effect on the average "tenderfoot," especially when lady 

 tourists, as not seldom happens, find their long hair slip from the 

 fastenings and stand up like the fabled head-dress of the Furies. 

 I have repeatedly heard the sounds at elevations between 6,000 

 and 7,000 feet, but they are much more noticeable at higher eleva- 

 tions, where they are sometimes terrific. They sometimes mark 

 the tension of the air just preceding a discharge of lightning, but 

 in general they are harmless. I have many times noticed them 

 proceeding with hardly any interruption while the lightning was 

 leaping from cloud to cloud overhead. They are caused by the 

 passage of an electrified cloud, and the effect is rather worse when 

 one is in the midst of the cloud. On these mountains the mani- 

 festation of intense electrical phenomena is seldom seen except 

 when there is hail or pellet snow, or the most violent summer 

 showers ; and the latter usually have hail in some part of the 

 storm. The loudest buzzings I have ever heard came while a 



