5 74 



THE POPULAR SCIENCE MONTHLY. 



part of the soluble vegetable matter are 

 albuminous in character, and the chemical 

 effect on the water is to increase the amount 

 of what is called "albuminoid ammonia." 

 No doubt dead fishes and animalcules and 

 their excrement add to the nitrogenous 

 organic matter in surface-waters, but their 

 presence is not necessary to account for 

 bad odors. As a rule, in waters not con- 

 taminated with sewage, the animal matter 

 forms only a trifling proportion of the en- 

 tire organic matter, but the recent investi- 

 gation of Professor Remsen shows that in 

 some instances the animal matter, as from 

 sponges, may be appreciable and of prac- 

 tical importance. 



Old and 3Vew Latitudes on the Atlantic 



Coast. The Rev. Edmund F. Slafter, of the 

 New England Historic Genealogical Society, 

 has published an inquiry into the history 

 and causes of the incorrect latitudes as re- 

 corded in the journals of the early writers, 

 navigators, and explorers relating to the 

 Atlantic coast of North America. After 

 giving comparisons of the old with the new 

 and corrected latitudes of a considerable 

 number of places, he sums up bis conclu- 

 sions that the early latitudes are generally 

 trustworthy to within a single degree ; that 

 the minutes or fractions of degrees as set 

 down by writers anterior to the middle of 

 the eighteenth century are never to be 

 relied upon, and are never correct, except 

 by accident ; and that the annotations of 

 commentators upon the latitudes recorded 

 in the journals of our early navigators and 

 explorers, in all cases in which they at- 

 tempt to identify places within the limit of 

 one degree by the latitude alone, can not 

 properly be cited as authority. The sources 

 of the errors of latitude to which attention 

 is thus directed are not far to seek. The 

 instruments possessed by the earlier navi- 

 gators were of the rudest and coarsest 

 character. They were graduated in degrees 

 only, of which each degree occupied but 

 about one tenth of an inch of space, and 

 t'le attempt to subdivide this space into 

 sixty parts, for minutes, would have been 

 impossible if it had been made. So, putting 

 down the fractions of degrees, or minutes^ 

 was an absolute and sheer guess. In the 

 old journals the minutes are usually written 



in fractions of a degree, as one fourth, one 

 third, one half, two thirds, or three fourths, 

 and sometimes translated into minutes, and 

 given as fifteen, twenty, thirty, forty, or 

 forty-five minutes, but very rarely in any 

 number of minutes not represented by these 

 general fractions. The zodiacal ephemeris, 

 moreover, was not graduated in minutes, 

 and consequently inaccuracy existed as to 

 the exact point of the sun in the zodiac at 

 the time of taking the latitude. The tables 

 used in connection with this instrument, 

 moreover, were not calculated oftener than 

 once in thirty years, so that they became 

 obsolete long before they were put away, 

 by reason of the precession of the equi- 

 noxes. Several other sources of error of 

 minor importance, now always allowed for, 

 were neglected in those days. " If the 

 latitudes of the early navigators," the 

 writer adds, "had been determined with 

 as much accuracy as is attained by the 

 observations of the present day, some in- 

 teresting historical questions might have 

 been settled, and some not very decisive 

 controversies might have been avoided." 



Word-Blindness. M. Armaignac has 

 described a curious case of persistent " word- 

 blindness." The sufferer is and always has 

 been in the full enjoyment of his intellect- 

 ual faculties ; he has never had any trouble 

 in his speech or from paralysis ; and he 

 writes correctly, in a regular and elegant 

 hand, whatever is dictated to him or what- 

 ever is his own thought ; but, although his 

 vision is perfect and normal, he can not see 

 a single printed word or a written one, 

 whether it be written by himself or another. 

 He recognizes the names of the letters and 

 figures, but can not join them objectively to 

 form words or numbers ; yet he can form 

 words and numbers mentally if the letters 

 or ciphers are dictated to him. M. Armai- 

 gnac has advised his patient to learn to read 

 again, beginning with the alphabet ; but he 

 finds the intellectual strain of joining the 

 letters into words and syllables very severe. 



Harvest-Time. Every season is a har- 

 vest-time in some country on the globe. In 

 Australia, New Zealand, Chili, and some 

 other countries in South America, the har- 

 vest takes place in January. In India, it 



