322 



NA TURE 



\ August 5, 1880 



in a column, the lowest one can be removed without 

 making those above it fall, by hitting it aside with a very 

 rapid stroke with a table-knife. Here again a feeble 

 stroke will fail. 



Our second figure illustrates inertia in another way. 

 A heavy metal ball is hung by a thread to the ceiUng or 

 to a shelf, and another thread is attached below. Tug at 

 the lower thread, and it will break. If the tug be slow the 

 ball will come down too ; but if the tug be sharp and fierce 



the thread will break off bcloiu the ball, breaking, in fact, 

 before the pull has time to impart to the mass of the heavy 

 ball a sufficient moving energy to enable it to rupture the 

 string by which it hangs. 



Many other illustrations of a similar kind might be 

 narrated. Of these probably the most telling is that of 

 firing a tallow candle from a gun through a deal board, 

 in which it leaves merely a hole, as the writer can testify 

 from several repetitions. Here, however, we are passing 

 into the region of" apparatus," and must not pursue the 

 matter further. 



CO UNT POUR TALES 



" T N the death of Louis Francois de Pourtales science 

 ■•■ has met a heavy loss. He was the Swiss repre- 

 sentative of an old family, which had branches also in 

 France, Prussia, and Bohemia. Trained as an engineer, 

 he emigrated in early manhood to the United States 

 at nearly the same time as the late Prof Agassiz, to 

 ■whom he was much attached, and whose pupil and 

 fellow-worker he was. He entered the Government 

 service in the department of the Coast Survey, and 

 continued in it many years. His talents and industry 

 made him a man of mark, to whom was intrusted much 

 work that required original thought. Especially did he 

 show interest in the problems of deep-sea soundings and 

 the structure of the ocean bottom, an interest that led to 

 profdund observations on the physical geography of the 

 Carribean Sea and the Gulf Stream. His papers on this 



subject were of the first order, and established his reputa- 

 tion in Europe as well as in .-Xmerica. 



" By the death of his father he succeeded to the title, 

 and received a fortune which enabled him to devote 

 himself wholly to his favourite studies, and to do much in 

 continuing the great work of Louis Agassiz. Appointed 

 keeper of the Museum of Comparative Zoology, he gave 

 himself, with untiring devotion, to carrving out the 

 arrangement so laboriously planned by his friend and 

 master. Dividing the task with the curator, Alexander 

 Agassiz, he pushed forward his part of the work with the 

 easy power of a strong and highly-trained intellect. 

 Every day and all day at his post— now pursuing special 

 investigations, and now directing the details of the 

 museum — he was the model of an administrative officer. 



" He had not an enemy, and could not have had one ; 

 for, although firm and persevering in temper, he pos- 

 sessed the gentleness of a child and a woman's kindness. 

 His modesty amounted almost to a fault ; and people 

 wondered why a man who was master of three languages 

 should talk so little. But with intimate friends he would 

 speak freely, and never without giving information and 

 amusement. His range of learning was very wide, and 

 his command of it perfect ; nor was it confined to mathe- 

 matics, physics, and zoology. He did not scorn novels 

 and light poetry, and was knowing in family anecdotes 

 and local history. Indeed, it was a saying in the Museum 

 that if Count Pourtales did not know a thing it was useless 

 to ask any one else. 



'■' His strong frame and temperate mode of life gave 

 hope of a long period of usefulness, for he was only fifty- 

 seven, and in the prime of his powers. But it was not to 

 be. Stricken, without apparent cause, by an obscure 

 internal disease, he succumbed, after some weeks of 

 suffering heroically endured. In seven short years he has 

 followed Louis Agassiz, and there seems no hand to take 

 up h s burden." 



The above account of Count Pourtales appears in the 

 Bos/on Daily Adi'criiser of April 20, and is, we believe, 

 from the pen of Prof Theodore Lyman. We would 

 here, in addition, refer briefly to some of Count Pourtales' 

 scientific work. Almost from the commencement of his 

 connection with the United States Coast Survey he deeply 

 interested himself in deep-sea questions, and some of the 

 earliest observations on the nature of the deep sea bottom 

 and of Globigerina mud were made by him. He wrote 

 on the structure of Globigerina and Orbulina, and de- 

 scribed the occurrence of the small Globigerina-like 

 shells bearing spines in the interior of certain Orbulinje, 

 which he concluded were the sv.-oUen terminal chambers 

 of Globigerinre containing young in progress of develop- 

 ment. The first step in deep-sea investigation in the 

 United States was taken by the late Prof H. D. Bache 

 on his assuming the duties of the United States Coast 

 Survey in 1844, when he ordered the preservation of 

 specimens brought up by the lead. Every specimen was 

 carefully preserved and labelled, and deposited in the 

 Coast Survey Office in Washington. The microscopical 

 examination of the specimens was commenced by the 

 late Prof. J. V.'. Bailey, and after his death this work 

 passed into the hands of Pourtales, who devoted his 

 time to it in the intervals of other duties. That most 

 important deposit, Globigerina mud, was first disco- 

 vered by Lieutenants Craven and Maffit, U.S.N., during 

 Gulf Stream explorations in 1853. In 1867 syste- 

 matic dredging in deep and shallow water was com- 

 menced on the assumption of the superintendence of 

 the Survey by Prof B. Pierce, who ordered the dredging. 

 At the suggestion of Louis Agassiz, dredgings were made 

 down to a depth of 1,000 fathoms. In Prof Agassiz' 

 report one of the richest grounds for deep-sea corals, lying 

 off Cape Florida, was named Pourtales Plateau. In 1S71 

 Pourtales published what is probably his best-known 

 work, namely, his "Deep-Sea Corals" ("111. Cat. Mus. 



