LITERARY NOTICES. 



559 



visions of time and movements of the heav- 

 enly bodies," the location of Vinland might 

 be a matter of doubt ; but it is fixed not 

 only by their description of the coast and 

 character of the country, but by the account 

 of Leif and his comrades, that " on the short- 

 est day the sun was in the sky between 

 Eyktarstad and Dagmalastad," periods cor- 

 responding to 4.30 p. m and half-past 7 a. m., 

 making the latitude 41 43' 10", nearly that 

 of Mount Hope Bay. Ancient vessels that 

 have been exhumed in Denmark, as well as 

 measurements found in the Sagas, prove 

 that the ships of the Northmen were able 

 to bear them across the Atlantic. That no 

 enduring structure marks their occupation 

 of New England is not astonishing ; accord- 

 ing to the story of their sojourn, they lived 

 in wooden booths. 



The literature and general knowledge of 

 the Icelanders were much in advance of the 

 rest of Europe during the twelfth century, 

 so that it is altogether credible that they 

 wrote the Sagas and performed the voyages 

 recorded. A corroboration of the Iceland- 

 ic writings is also found in early English 

 annals, which contain statements and dates 

 that exactly agree. The manuscript from 

 which the Sagas are taken is the Codex 

 Flatoensis, " a work that was finished in 

 1395 at the latest, . . . and now preserved 

 in the archives of Copenhagen." 



The latter part of Dr. De Costa's work is 

 devoted to translations from these writings, 

 relative to the pre-Columbian voyages. Ex- 

 tracts are given from the Landanama,'the 

 doomsday-book of Iceland ; from the Sagas 

 of Eric, composed in Greenland ; and from 

 the Saga of Thorfinn, of Icelandic origin. 

 Following these are minor narratives taken 

 from the Eyrbyggia Saga, and two geographi- 

 cal fragments that mention Vinland. Al- 

 though the volume possesses an index, it 

 has the unusual distinction of being a book 

 without chapters. 



Dust and its Dangers. By T. Mitchell 

 Prudden, M. D. New York : G. P. Put- 

 nam's Sons. Pp. 111. Price, 75 cents. 



The author of this book does not discuss 



purely inorganic dust of any sort, not even 



the specially injurious kinds resulting from 



processes of manufacture, but in a simple 



and attractive way tells of the common dust 



that is dangerous that which contains 



micro-organisms hurtful to man. He de- 

 scribes the classes of germs that can be 

 identified, and explains how biological anal- 

 yses of the air are made by the " filtration " 

 and the easier " plate method." Comparison 

 of averages obtained in various cities and in 

 different localities in New York show that the 

 number of bacteria in a given volume of air 

 varies chiefly according to condition, the pro- 

 cess of street-cleaning summoning the great- 

 est number of germs, 5,810 to a disk 3f- 

 inches in diameter. Indoor air is, however, 

 the main subject of investigation, and ex- 

 periments prove that ventilation which com- 

 pletely changes the atmosphere three times 

 an hour will not appreciably affect the num- 

 ber of bacteria in an apartment, as the in- 

 truders cling obstinately to the carpets and 

 upholstery. Only violent currents of air dis- 

 lodge these, and the sweeping and cleansing 

 which result in removing, not redistributing 

 the dust. Ordinarily we are liable to take in 

 with every twenty breaths from eleven to 

 eight hundred and seventy-six organisms. 



Among the disease - breeding bacteria 

 Dr. Prudden selects for study the one num- 

 bering most victims, the Bacillus tubercu- 

 losis. He points out that prolonged drying 

 does not kill it ; that it does not exist in 

 the air exhaled from consumptive lungs, 

 but in the sputa that is ignorantly allowed 

 to become part of the dust. It results that 

 " the way to most efficiently stop this dis- 

 tinctly preventable disease is to see that the 

 sputum of consumptives is properly dis- 

 posed of." 



One of the most instructive chapters is 

 that in which the action of the cilia, of the 

 lymph-filters, and of the wandering white 

 cells, is described. A number of illustra- 

 tions and an index accompany the book, 

 which is published in uniform style with 

 The Story of the Bacteria, by the same 

 author. 



Kaces and Peoples. By Daniel G. Brin- 

 ton, M. D. New York : N. D. C. Hodges. 

 Pp. 513. Price, $1.75. 



A series of lectures, delivered at the 

 Academy of Natural Sciences, in Philadel- 

 phia, during the early months of 1890, forms 

 the basis of this book. In the first two 

 lectures are given respectively the physical 

 and the mental characteristics of races, upon 

 which ethnography is based. The third iect 



