546 



SCIENCE. 



[N. S. Vol. XVH No. 431. 



It was decided to revise and enlarge the ex- 

 change list of the academy Transactions. 

 G. P. Geimsley, 



Secretary. 



DISCUSSION AND CORRESPONDENCE. 



THE ACTIVITY OF MONT PELEE. 



The generally friendly tone of yoiir re- 

 viewer's (T. A. J., Jr.) notice of my ' Mont 

 Pelee and the Tragedy of Martinique ' makes 

 it almost ungenerous on my part to take ex- 

 ception to any of the statements that this 

 notice contains. There is one point, how- 

 ever, dealing directly with the physics of 

 Mont Pelee, that seems to me to deserve at- 

 tention from its bearing upon volcanic phe- 

 nomena generally. Your reviewer takes 

 strong exception to the use that I have made 

 of Eussell's formula in computing the cubical 

 content of the ash-cloud, and remarks that 

 the defect in my reasoning ' lies in the as- 

 sumption that a primary eruption is con- 

 tinuous for days or even hours.' The some- 

 what surprising statement follows that : " Pro- 

 fessor Heilprin has failed to discriminate 

 primary and secondary eruptions when he 

 talks of Mt. Pelee ' being in a condition of 

 forceful activity for upwards of 200 days.' " 

 This does scant justice to my powers of ob- 

 servation, for it takes no scientist to separate 

 or discriminate between the two classes of 

 phenomena, any more than it requires a sci- 

 entific eye to note the difierence between the 

 explosion of a dripping drop from a ' boiling 

 kettle ' and the ' blow ' that issues from the 

 snout. I fear that Dr. Jaggar has not seen 

 Pelee in 'Pelee's glory,' otherwise he could 

 hardly have hazarded the statement to which 

 attention is called, and still less the subse- 

 quent one that ' the reviewer questions 

 whether the volcano has been forcefully ac- 

 tive from great depths for that many [200] 

 minutes.' Had Mr. Jaggar been on the 

 island of Martinique at any time during the 

 days August 25 to September 3, inclusive, his 

 conception of a ' primary eruption ' would be 

 very different from what it manifestly now 

 is — he would have seen a raging central erup- 

 tion continuous for that time, and not a 



landscape of ' tremendous puffs that rise many 

 thousand feet.' 



When I prepared the chapter of my book 

 which contains the calculations to which my 

 reviewer takes exception, I was unaware of 

 the conditions of the volcano which followed 

 after my leaving the island. These are in 

 many ways most interesting, and tend to 

 confirm my conclusions as to the extraordinary 

 quantity of" the sedimental discharge from 

 Pelee. The continuous activity of the vol- 

 cano has been such that in the interval be- 

 tween the first week in September and the 

 middle of December the mountain had in- 

 creased its height by nearly or quite 900 feet 

 (!), the needled summit of the cone (which 

 had united with the old crateral wall) being 

 on December 16, as measured by Lacroix, 

 4,995 feet above sea-level. Much of this has 

 since been destroyed, but Pelee is still at its 

 work, adding to the 300 feet of ash that it 

 has already laid down in parts of the valley of 

 the Riviere Blanche. I do not think that 

 the volcano can be seriously accused of work- 

 ing in working times of ' five or ten minutes.' 

 In the days of the August-September activity, 

 I feel satisfied — although necessarily lacking 

 the means of proving the accuracy of my be- 

 lief — that the continuous ash-discharge could 

 not have been less than twenty per cent, of 

 the measure of the steam-cloud; it may have 

 been very much more. 



Angelo Heilprin. 



Philadelphia, Pa., 

 March 17, 1903. 



THE PUBLICATION OF REJECTED NAMES. 



I AM glad to see Mr. Bather's letter, al- 

 though I can not altogether agree with what 

 he says. My view is that if a description ap- 

 pears, accompanied by two or more names in 

 the same publication, all being simultaneous 

 in point of time, nothing but ' priority of 

 place ' can furnish a certain and invariable 

 rule for selecting the one to be retained. I 

 do not want to disturb existing rules, but I do 

 want to see the same rules in use for all 

 groups of animals and plants. My objection 

 to the action of Messrs. Banks and Knowlton 

 was based on the fact that they seemed to me 



