34 CONTRIBUTIONS TO THE NATUEAL HISTORY OF ALASKA. 



northeast winds in October throws huge winnows of sand on the beach, and are not conformed 

 with the general level until the following spring. 



It is rare that more than one tide occurs in a day, and in those times is what is termed a 

 long and short tide. 



The usual time of high water occurs fifty minutes later each day, though there are so many 

 exceptions that it cannot be given as a rule. 



For several days the rising of the tide is shortened in time, and floods at nearly the same 

 hour for several days. No positive rules can be laid down by me on the tides. 



KAINBOW. 



This spectacle occurs seldom, by reason of the entire cloudiness during rain. In summer the 

 bow is sometimes complete, and does not differ from those in lower latitudes. In winter au arc of 

 10 to 20 degrees will sometimes be seen, and on one occasion, when only a slight rift toward the 

 sun made opposite to it a rainbow whose length was scarcely half its width. 



In November, 1874, an arc of 15 degrees in height was seen, and besides the primary bow there 

 were three supernumerary bows of variable colors, as given in the journal for that day. 



I can conceive of no more beautiful object in nature than this spectacle so brightly displayed 

 against a sky of leaden hue. 



The fog-bow is sometimes seen during the day, and on several occasions after night. Only 

 once, and then after night, did it incline toward prismatic coloration, and that of faintest red. 



OORON^E. 



Coronse have never been seen, excepting surrounding the moon. A white mass of stratus in 

 winter, if not of too great density, produces this phenomenon in its greatest brilliancy. The 

 different rings are of variable width. 



HALOS. 



I shall divide the halos into three classes, according to intensity or absence of coloration. 



A pure white halo of 22 degrees often occurs during a time of clear upper sky and the lower 

 atmosphere filled with finest frozen fog-like particles. It is probably due to the smallness of 

 these particles that the halo is colorless, for the same reason that a fog-bow should be white. 



A second kind of halo occurs frequently, which I have recorded on the Form 4 as a dark halo 

 of 22 degrees. It usually occurs during a very dense streaked cirri veil, and increases to such 

 density as to obscure the sun. 



In my earlier days I have frequently noticed that if a piece of perfectly clear ice is held at a 

 certain angle, and looked through edgewise, it appears black. I now venture to suggest that the 

 films of ice in the atmosphere were descending at this angle, and hence the halo appears dark. 

 The inner edge of the ring is usually whitish, but the line dividing the dark and white circles is 

 very apparent to an observer. 



This halo aud the first mentioned halo are always without parhelia or contact arches. 



The third class comprises all the halos that exhibit prismatic colors. 



The sun during the season for this phenomenon does not rise sufficiently above the horizon to 

 permit an entire halo of 22 degrees to be observed, but it has frequently descended to the ground 

 and not distant half a mile; and was one time, as previously referred to, seen on the ice at a 

 diverging angle; probably the reflection of the portion in the air. The halo of 45 degrees has 

 been recorded several times. These two alone present coloration, oftentimes very brilliant, but 

 always less so on the one of 45 degrees than on the one of 22 degrees. The parhelic circle has 

 been seen complete on two occasions, and always white. 



Parhelia at the intersection of the two halos are common enough ; often the tail is prolonged 

 to several degrees. The coloration of these is extremely bright, and sometimes so brilliant as to 

 dazzle the eyes. The contact arch is seen only above the suu for reasons stated before. 



These are more noticeable during the descent of frost films, and are best observed by looking 

 over the top of a building to hide the sun. 



The "horns" are fully developed, with the lenticular space well preserved. They exhibit 



