AUQU~T, 1897. MONTHLY WEATHER REVIEW. 363 had been partly converted into water in consequence of the rising tem perature. The rain water that fell with the particles of ice soon frozt to smooth sheets of ice. The hail in question gradually accumulated to a thick layer. Ii consisted of an extraordinary large number of small spheres, generallj only a few millimeters in diameter, which, by their clear transparency, presented a very beautiful appearance. The little s heres la at firsi close to each other on the ground and were rolled alout by t l e wind, Afterwards, by partial thawing and freezing or by freezing the watei between them, they adhered to each other and thus produced the im. pression of transparent fish roe. The perfect clearness of the dainty dro s of ice made it improbable that they would have a radial structure &e the s hereolites. Undei the microscope many of these, as seen by polarizeflight, were demon. strably composite, but B great number, on the other hand, and espe. cially the smaller ones, seemed to be simply and uniformly constructed out of one single cryRtal of ice. We have, therefore, here a remarkable caae of individual spherical crystals which, in opposition to the ordi. nary angular form of the crystal, possess an outer surface of uniform curvature, so that a description in crystalographic nomenclature could only be obtained after a ph sical determination of the axes. These little s heres under olarizeY light, viz, between crossed nicol prisms, showef ver beauti& rlarization phenomena; as they were not hol. low, they &owed in t e center the hipher colors, for instance, the green of the second order and diminishing outward in ring-like zone€ they showed the lower colors in gradual transition. The changing 01 larization colors as the ice spheres melted was especially E Z i G . The extinction of the light as the analyzing prism was turned w a ~ smooth and clean, so that, considering the positive double refraction of the ice, the meridian plane of the sphere could easily be determined. Those spheres that lay in appropriate positions u on the stage of the microscope showed in converging polarized light &e phenomena char- acteristic of optical uniaxial crystals, and by testing with a thin plate of gy sum, corresponding with the red of the first order, showed posi- tive fbuble refraction. Some of the ice particles were bounded by a circular plane surface and a portion of a spherical surface. They were, therefore, certainly only pieces of hailatones, but as it was precisely these that showed the black cross with bright rings when examined with conve ing olarized light as they lay upon their flat faces, it would seem aa%oug% the re- s ective spheres in consequence of their cleavability had been cloven afong one of their principal planes by striking other hard bodies; at least this explanation seems to me more robable than that of an original hemimorphic structure in the cry stai. The complex ice spheres showed in polarized light a honeycomb appearance, whence it may be inferred that the7 were made up of a number of nucleii; the arran ement of the nucleii was irregular. Oc- casionally in such a little spfwre of ice there would be remarked a needle of ice whose location in reference to the sphere seemed not to be arranged according to any law. The needles or bars of ice them- selves showed that they were built up of nucleii irregularly arran ed. Microscopic round and irregular-shaped bubbles of air collectefi in groups on the surfaces were quite frequently found, notwithstailding the extreme clearness of the ice formation. As to the question of the origin of the s herical crystals of ice and the crystalline bars it can not be doubted &at we have to do with fro- zen drops of rain. I have attempted to make such frozen spheres artificially. If we allow a dro of distilled water that is hanging at the end of a delicate thread, an$ that forys a nearly spherical ball, to freeze, we obtain a clear sphere of ice. rhese artificial formations all prove to be com- plex in their structure. I n their mode of occurrence the above-mentioned spheres of ice re- mind one in some respects of the chondrule of meteoric stones. (The chondrules are small spherical grains of foreign minerals often with an imperfect radial Atructure imbedded in meteoric stones.) The his- tory of the origin of these forms is probably.also analogous to that of the spheres of ice, in so far 8s they are frozen drops. The sphere of ice aa a unit corres nds especially to the monosomatic chondrule of Tschermak, in whicc the whole of the little sphere is built up of one round crystal aa a unit. The rest of Professor Rinne’s article relates to the struc- ture of meteors rather than to that of hailstones. If we may pass from his study of this particular case of sleet and hail to the larger hailstones that accompany American thun- derstorms, one might infer the probability that the latter, upon examination with polarized light, would also be found to have a composite structure. But such matters should not be left to analogy or hypothesis. It is very much to be de- sired that the numerous physicists of our colleges and schools of science should apply their elaborate outfits of optical ap- paratus to the minute investigation of the destructive but magnificent hailatones that so frequently occur in connection with our violent thunderstorms. -0- THE! ANCIENT CLIMATE OF ARIZONA. In May last, Mr. 1%’. T. Blythe, Weat.her Bureau observer a t Phenix, Ariz., sent to the Central Office some specimens of seeds, cloth, and cord taken from a niummy found among the cliff dwellings of Arizona. In hopes that the nature of the plants to which these three objects belonged might be identified, and that something might result by way of infor- mation relative to the climate at the time these plants were living, the specimens were referred to the botanist of the Department of Agriculture. It was ascertained by micro- scopic examination that (‘ the cloth was made of cotton, but the cord accompanying it was made of a fibre that is not at present recognizable. The seeds appeared to be those of an Aramantus, several species of which are still in use for food by various peoples, including the Indians of the southwestern portion of the United Mates.” An effort was made to raise some plants from these seeds, but they failed to germinate. The general outcome of this study is simply to show that there is no evidence of any material change in the climate of Arizona since the days of the cliff dwellers. VITALITY OF 8EED8. Many stories are current in the newspapers of success in sprouting and raising plants from seeds found in Egyptian and Peruvian mummies or burial places, and even still more extravagant tales of plants raised from seeds buried many feet deep in the earth in strata that must have been laid to rest not only in the days of the glacial epoch but in still earlier geological ages, but not a single one of these stories has stood the teet of careful investigation ; either they were pure fabrications or the plants that actually grew belonged to modern flora and sprang from really fresh seeds; it is proper to say that the cautious botanist puts no faith what- ever in these stories, partly because the proper tests have not been applied, but principally because of the results of so many experiments that have been made with great care to test the vitality of ordinary seeds. Every farmer knows that the proportion of seeds that will sprout diminishes year by year the longer the seeds are kept, EO that a t the end of ten gears not one per cent of the ordinary seeds retain their vitality. There are indeed certain plants which in their wild Dr natural state have a vastly greater vitality than others, hut the seeds of food plants cultivated by mankind are among the most delicate. The molecular structure of seeds, and not only seeds, but almost every other substance, whether animal, vegetable, or mineral, undergoes a slow change with time. Wherever sunshine, air, and water can penetrate, there molecular changes are persistent.ly going on ; these changes are usually of the nature of a slow oxidation ; in the case of animal snd vegetable material buried under the soil, far away from 3unshine and air, there is a rearrangement of the molecules of :arbon, oxygen, and hydrogen, so that they become converted into coal oil and coal oil gas. It is contrary to nature that 3eeds should retain their vitality under these circumstances ; nevertheless the attempt to make them germinate should be made because i t does seem as though there might., by chance, 3e found one that had escaped decomposition. It is equally mportant to first subject ancient seeds and fabrics, wherever round, to a microscopic examination, since some minute ietail of structure may reveal the nature of the plants from which they came. In general, those Weather Burean observers and corre- ipondents who happen to be in a position to collect interesting nementoes of the early races that have inhabited this conti- lent would do well to refer their finds directly to the National 364 MONTHLY WEATHER REVIEW. AUQUST, 1897 Rainfall. Museum a t Washington rather than attempt any original investigations of their own, since the proper interpretation of archeological remains is a matter that has been found tc require the greatest caution and the most extensive knowledge, MAURITIUS-METEOROL0<3Y AND CROPS. We note that the annual report for 1S96 of the Royal Alfred Observatory, on the Island of Mauritius, comes to us with the signature of F. F. Claxton, assistant in charge of the Ob- servatory, he having been appointed first assistant a t the close of the year and entering on his duties on February 10, 1896. Since that date Mr. Claxton, who was formerly an assistant a t Greenwich Observatory, has been appointed ta the position of director, succeeding Meldrum, whose life work has made this Observatory so famous. In this annual report, for 1895, Mr. Claxton gives a table showing the mean annual rainfall for four stations on the Island as compared with the total crop of sugar for the corresponding calendar year, from 1880 to 1895, which we reproduce in the following table, except only that we have rearranged the figures in the order of the annual rainfall : -- Sugar crops. Year. Inches. (8.8 64.85 69.87 68.88 88.84 66.69 68.11 69.40 70.68 78.10 76.67 76.18 78.28 91.71 98.86 1ca.B h-ilograms. 1oB.m.211 1886 119,781,4@2 1880 121 784 889 1882 116'aoS:oS9 1886 18CI:751,810 1993 117 809 610 1631 118'796'819 1891 124'm'140 18Bi 18o'm'm 1880 1aa:aaa:Sao 1- 190,898,858 1868 68 7l8,678 1892 118'818 lV6 la1 124'ti64'%51 1889 116'719'997 1888 Ia8:l~See 18BB I I If we divide this series of figures into three groups of fivc each, omitting the year 1892, when a disastrous hurricane occurred on the 39th of April, we obtain the following aver. ages which give us some idea as to the importance of the lrnMd ysa~ cmragse. Rainfall. S u j p r crop. I Date. I annual quantity of rainfall. These averages, as will be seen by the dates of the average crop year, partially eliminate any progressive change in the area devoted to the sugar crop, the style of agriculture, or any other slow change that is goin! on, and we may infer that the increase of annual rainfall from 55 to 90 inches has had approximately no effect in increasing the total crop. But this must not be misunderstood as i m plying that rainfall has nothing to do with crop production, The fact is that the sugar cane requires about eighteen monthf for ripening from the time of planting. A field that if planted in September will be gathered in June of the second following year. The crop then gathered must be compared with the rainfall during those eighteen months, and, more especially, during the middle portion of that interval. It i f evident, therefore, that the comparison which we have been able to make, as suggested by Mr. Claxton's figures, is not a fair one, and that the subject must be pursued with more de- tail, very much as was done by Ramson and Walcott in their studies upon the sugar crop of Barbadoes. A similar remark must be made with regard to the major- ity of the compilations of statistics that have been made by those who would elucidate the relation between climates and crops. The rainfall, temperature, humidity, sunshine, and the condition of the soil must be discussed separately for the four divisions of the plant's life. The matter is too complex to be treated by means of crude statistics without an intel- lectual perception of the laws of plant growth. As the drought of 1896 in Mauritius was but one item in the destmctive drought that prevailed all over the South Pacific, as well as over parts of the Northern Hemisphere, the Editor reserves his discussion of that important subject for the next REVIEW. -ct PRACTICat SCIENCE IN GERMANY. In the MONTHLY WEATHER REVIEW for April, 1896, Vol. XXIII, p. 131, we have dwelt upon the importance to the farmer, and for that matter to the whole country, of the establishment of some Governnient office-a bureau where the useful efficiency and relative value of machines for agricul- tural purposes may be thoroughly and officially determined- analogous to the Bureau of Weights and Measures and the offices for testing seeds, investigating fibres, testing the strength of woods, extirpating dangerous diseases, etc. Somewhat analogous to these latter various bureaus that have from time to time.been established in the United States, is the one central institiition that has been founded in Germany under the name of the Physical-Technical Institute, which is located a t Charlottenburg (formerly a suburb but now in- cluded as a part of the city of Berlin), the province of which is to carry out scientific investigations and practical tests that are beyond the reach of the ordinary laboratory, and that are of fundamental or general importance to the whole country. The following is an abstract of a report prepared by the United States Consul-General a t Frankfort, Germany, Frank H. Mason, and published in the number for July, 1897, of the Consular Reports of our State Department: From the series of expert investigations that have been made during the paat two years by English economists and commissions to ascertain the underlying causes of Germany's rapid and ominous advance as a manufacturine nation, one definite conclusion has been convincingly drawn. This IS, that, putting aaide all questions of protective duties, comparative wages, supply of native materials, etc., Qermany, as an industrial nation, en'oys in two respects diatinct advanta e8 over Great Britain and every otber European country. These are 'Hrst, the wide diffusion and high standard of technical and industriai education pro- vided in this country; and second, the liberal and intelligent support that is given by the imperial and various state governments to the d e velopment of theoretical science and the higher and more scientific forms of industrial enterprise. In support of the latter of these propositions, and as an illustration of how far a moderate expenditure of money, under Government au- thority, can be made to reach in the advancement of scientific inveati- gation and the promotion of engineering and kindred enter rises, the Imperial Physical-Technical Institute at Charlottenburg, Serlin, ie cited aa the highest existing example of its clam, and a model for the study and imitation of other governments which are seekin , aa Ger- many has done since 1856, to prepare and equip their peopfe for the industrial struggles of the future. The introduhon into Conpees of a measure like the Hale engineer- ing experiment station bill is a sign that in our own country the need of Government aid in this direction is recognized, and the following brief account of the plan and functions of the great parent institution at Charlottenburg ie submitted as a contribution to a movement that has been alread initiated. The Physika8sch-Technische Reichsanstalt to use ita German OB- cia1 designation, was founded in 1887, mainly through the influence of the eminent electrician Werner von Siemens, who gave for the ur- chase of the site of the institute 500,000 marks ($119 OOO). The srst president of the institution was the renowned phys)icist, Prof. Her- mann L. F. von Helmholtz, who since his death in 1895, has been eucceeded by Prof. Dr. Friedrich dohlrausch. The institution comprises two sections, aa follows: The physical de- partment, which haa for its field the advycement of pure science, or, in the language of Professor Helmholtz, the prosecution of scientific