372 



SCIENCE. 



[Vol. XX. No. 517- 



In which k is some constant. Substituting from (1) we obtain 

 1 _ C?a= - Ay'- 



da'^ sin ■ 



in which these occur, is equivalent to saying, the sum of the 

 angles of a plane triungle is constant and equal to two right-angles. 

 This hypothesis leads to the Euclidean, or parabolic, geometry, 



angles of a plane triangle is less than two right-angles, and leads 

 to Lobatschewsky, or hyperbolic, geometry. Finally, the hy- 

 pothesis j^ > makes da > dy and indicates that the sum of 



the angles of a plane triangle is greater than two right-angles. 

 This gives rise to the elliptic geometry. The last is divided 

 into two divisions — the single elliptic geometry and the dou- 

 ble elliptic geometry. The names parabolic, hyperbolic, single 

 elliptic, and double elliptic were applied to these spaces by Klein. 

 The last two kinds of space are nearly alike. Euclidean geome- 

 try may be regarded as the common limit of the hyperbolic and 

 the elliptic geometry. Considerations similar to the preceding 

 lead to four kinds of re-dimensional space, and hence there are 

 four kinds of n-dimentional geometry. 



ALTAKAPAS COUNTRY. 



BY JOHN GIFFOKD, SWATHMOKE COLLEGE, PA. 



In the southern part of Louisiana there is an interesting region 

 called the " Altakapas Country" It was once inhabited by a 

 tribe of Indians of that name. They have the reputation of hav- 

 ing been cannibals, but the later generations were peaceful and 

 industrious. A few of them, they say, still exist and are famous 

 for the skilful manner in which they make a peculiar kind of 

 basket-work. Specimens of this may be seen in the museum of 

 the Tulane University of Louisiana. . 



Roughly speaking, the region referred to embraces the land 

 bordering the Gulf, west of the Atchafalaya and east of the Mer- 

 mentan River. There is some discussion as to the extent of the 

 country known by that name. As ordinarily used the term is 

 elastic, but in a map printed in 1826 it includes all of what was 

 then known as La Fayette, St. Mary's, and St. Martin's parishes 

 and what is now known as Vermillion, La Fayette, St. Martin's, 

 and St. Mary's. 



Kxcepting five islands to which I shall refer later, this country 

 is low, level, and rich. It is a part of the alluvium of the delta, 

 which is intersected by many bayous, the arteries of Louisiana. 

 The Atchafalaya is sometimes called " Old River," and was once 

 no doubt the bed of the Mississippi. To-day it is reddened by 

 the water from the Red River, in the mouth of which it begins. 

 It is now perhaps the largest collateral artery of the main trunk. 

 It was once clogged by an enormous raft, which was removed by 

 the State in 1835. According to LeConte, it "was a mass of 

 timber eight miles long, seven hundred feet wide, and eight feet 

 thick. It had been accumulating for more than fifty years, and 

 at the time of its removal was covered with vegetation, and even 

 with trees sixty feet high." 



The Altakapas country consists of tilled lands, low meadows, 

 and sea-marshes. The thriftiest of the first extends along that 

 tortuous, sluggish stream called Bayou Teche. It is very rich 

 and well cultivated, and by many is considered the garden-spot 

 of the State. The banks of the Teche are lined by beautiful 

 sugar plantations with old-time palatial residences and many 

 modern refineries. -Cane is there worked, and sugar and mo- 

 lasses manufactured according to the latest scientific methods. 

 Enormous quantities of sugar, molasses, rice, cotton fibre, oil, 

 and meal, and cypress lumber are shipped from this region. Even 

 the moss on the trees is the source of an income of no little con- 

 sequence. 



This bayou begins in a network of streams in the Red River 

 country and empties into the Atchafalaya below Grand Lake. 



Tn few places in the world will you meet with such scenery. A 

 trip do^vn the Teche from St. Maitinsv ille, a quaint town grey 

 with age and '-finished" long ago, once cnlled " ihe little 

 Paris, the land of Evangeline."' on a sugar-packet is claimed 

 by many, for scenery of its kind, to be unrivalled outside of 

 Louisiana. 



West of the Teche are miles of meadow-land, where many 

 here's of horses and cattle pasture. South\vard bordering the 

 bays and Gulf is a region of sea-marshes and floating prairies. 



In the midst of this marsh, near Vermilion and Atchafalaya 

 Bays, there is a chain of five islands, the highest land in lower 

 Louisiana. The most western is called sometimes Miller's, 

 sometimes Orange, and sometimes Jefferson's Island. It is the 

 centre of Joseph Jefferson's famous plantation. The second is 

 called Petite Anse or Avery's Island, where the Avery salt mine- 

 is located, the like of which, the.y say, does not exist in this coun-- 

 try. The third is Week's Island, the fourth Cote Blanche, and- 

 the last Belle Isle. 



The fact that five islands exist, much different from the sur- 

 rounding country, of a different formation, in a straight line, 

 about six miles apart, in the Mississippi Delta is curious. But- 

 stranger still the core of Avery's Island is a mass of rock salt of 

 the purest kind, the only impurity, in fact, is .120 per cent of 

 gypsum. 



While prospecting for the opening of another mine, they 

 found the bones of the mastodon, giant sloth and perhaps of 

 other extinct .nnimals in layers of material of a peaty nature. 

 Here, also, were found beautiful potshei-ds and kitchen middens- 

 of the Indians who once lived there. There were also indica- 

 tions, I was told, that the Indians knew of the presence of this- 

 salt, although, according to Dr. Hilgai-d, it was not discovered 

 by the whites until 1863. The bones and potsherds which were 

 found there are now in the museum of the Tulane University of 

 Louisiana. 



To scientists and sightseers these mines are well worthy a visit, 

 but unfortunately are rather inaccessible. It is easiest reached: 

 from New Iberia on the Southern Pacific Railroad There is a 

 freight train running to the mines, which carries a passenger 

 car. This remains, however, only long enough to collect the 

 freight, which is seldom more than thirty minutes. There is 

 only one train daily. The wagon-road is dangerous at times and. 

 never pleasant for vehicles owing to much mud, bad bridges and 

 a pole-road over the mnrshes. The best way to reach it is on 

 horseback, and for this purpose the Acadian ponies have no 

 equal. They have a peculiar gait, faster than a fast walk, and' 

 lift their feet in a quick peculiar manner, which comes, they- 

 say, from pulling their feet quickly out of miry places. 



The i.-land is visible a long way off, and owing to the contrast 

 with the surrounding country is very striking and prominent. 

 The soil is pure sand and clay, in places mixed to form a 

 loam. 



To enter the mine you are apparently instantly dropped dovv-n 

 a shaft one hundred and seventy feet lieep. You are then in a, 

 huge cake of salt i-esembling ice. The weight above is supported' 

 by huge pillars of salt. Enormous quantities have been removed 

 and the supply seems exhaustless. In places it is as clear and 

 transparent as ice, in others granular, in others dark in color, 

 and in others in irregular waves as though contorted by pressure. 

 Here and there are pockets in which beautiful cubical crystals 

 may be found, some of which the writer collected were li x lA x t 

 inches in size. 



Although it affords ventilation, they have been troubled by a 

 slight cave, which of course gradually washes larger in size, and 

 a fine sand is thus washed into the mines. 



In the Smithsonian Contributions, Vol. XXIII., Dr. Eugene 

 Hilgard has described this- formation in a paper entitled "Ge- 

 ology in Lower Louisiana and the Salt Deposit of Petite Anse- 

 Island." 



One of the other islands borders on the bay, where there is a 

 bluff from which the formation may be studied. 



Over in the neighboring parish of Calcasieu, near Lake Charles, 

 there is a bed of sulphur which promises to become an important, 

 industry. 



