May 6, 1887.] 



SCIENCE, 



435 



— The well-known Wobum rotation experi- 

 ments, undertaken by Voelcker for the Royal 

 agricultural society of England, have been fre- 

 quently quoted as casting discredit upon the con- 

 clusions of the chemist regarding the manurial 

 value of different articles of cattle-food (see arti- 

 cle in Science, ix. No. 206, for an account of these 

 experiments). The manure from animals fed 

 with cottonseed-meal, in particular, showed no 

 superiority over that from animals fed with corn- 

 meal, although the former must have been much 

 the richer in plant-food. Those, however, who 

 interpreted the experiments unfavorably to the 

 conclusion of the chemist, forgot that the soil is 

 as important a factor as the manure in the pro- 

 duction of a crop, and that upon an already fertile 

 soil the direct fertilizing effects of manures may 

 have no opportunity to show themselves ; some 

 other factor being present in relative minimum, 

 and thus controlling production. In the last num- 

 ber of the Journal of the Royal agricultural so- 

 ciety, Voelcker reports briefly upon the begin- 

 ning of a similar experiment upon poor soil. Few 

 details are given ; but the general result was that 

 the manure from cottonseed-meal greatly sur- 

 passed that from corn - meal, thus indicating 

 strongly that the soil of the Woburn experimental 

 field was too rich for the proper conduct of ex- 

 periments with fertilizers, and giving a very plau- 

 sible explanation of the abnormal results reached. 



— A system of indicating the time at night 

 throughout a district lighted by electricity from a 

 central station has been patented by Patrick B. 

 Delany, an electrician of this city. The system 

 consists in causing all the electric lights in the dis- 

 trict to fluctuate in intensity, in a predetermined 

 manner, at proper intervals, and in such a way as 

 to indicate the hour. 



— Mr. E. C. Sanford of the Johns Hopkins uni- 

 versity has republished, with an introductory note 

 by Prof. Stanley Hall, his study of the manu- 

 scripts of Laura Bridgman, the famous blind deaf- 

 mute now living, at the age of fifty-seven, at 

 South Boston. The author has had access to al- 

 most all of the diaries and other writings which 

 Laura Bridgman has from time to time written, 

 and has given a valuable as well as interesting 

 analysis of their contents. Her autobiography is 

 given almost entire, and abounds in quaint errors, 

 such as normally constituted persons would sel- 

 dom if ever commit. These are sifted out and 

 presented with much tact, and the whole study is 

 an important contribution to the history of one of 

 the most remarkable educations through which a 

 human being ever passed. 



— About two years ago, Mx. de Nic^viUe of the 



Indian museum, Calcutta, sent for exhibition to 

 the entomological society of London several series 

 of Indian butterflies, which were universally re- 

 garded as distinct species, but which closely re- 

 sembled one another, excepting that the con- 

 spicuous ocellated spots of the under surface of 

 the wings of certain kinds found in the rainy sea- 

 son were replaced in other kinds which fly only in 

 the dry season by more uniform, paler, and leaf- 

 like markings, in which the ocelli are obsolete. 

 He regarded these as probable instances of sea- 

 sonal dimorphism, — a view which was vigorous- 

 ly combated by some of the members present at 

 the exhibition. He has now proved his right to 

 the belief in the case of four pairs, having raised 

 one series of forms from eggs of the other {Journ. 

 Asiatic soc. Bengal, 1886). These were species of 

 Yphthima, Mycalesis, and Melanites, and it is the 

 first time this phenomenon of seasonal dimorphism 

 has been shown in tropical butterflies ; it was 

 supposed to be altogether related to the winter of 

 temperate regions. Mr. de Niceville believes that 

 the obliteration of the ocelli is "an advantage to 

 the insects during the cold and hot seasons, as at 

 those times the vegetation is much more scanty 

 and dried up, the insects live chiefly among the 

 gxass, and would consequently be easily seen were 

 they not inconspicuously colored and marked ;. 

 while in the rains, the vegetation being then very 

 dense, they can hide themselves, and their con- 

 spicuous livery is no bar to their safety." De 

 Niceville adds at the end of his paper (in which 

 the early stages of Yphthima and Mycalesis are 

 for the flrst time figured) that he could indicate 

 " many dozens of Indian species" in which he be- 

 lieves seasonal dimorphism occui's, " including 

 nearly every family into which butterflies have 

 been divided," but he " might again be accused of 

 ' guessing.'" Here is certainly an interesting and 

 open field for the Indian entomologists, which 

 even the tyro may till. 



— Excavations for the foundations of the 1000- 

 foot iron tower to be erected in the Champ de Mars^ 

 Paris, are being made. Each of the four members 

 of the tower framework will rest upon a pyramid 

 of masonry 26.24 feet high, to which it will be 

 secured by anchor- bolts six inches in diameter.. 

 Four immense masses of beton, resting on a stra- 

 tum of clay nearly fifty feet below the surface^ 

 will serve as foundations for each of the masonry 

 pyramids ; and the enormous weight of the whole 

 will act as a counterpoise to insure the stability of 

 the tower against the great wind-pressure to which 

 it wiU be subjected. 



— Messrs. Ticknor & Co. , Boston, have recently 

 published, under the title ' American literature 



