250 



NATURE 



\yan. 27, 1876 



white flowers, 238 with yellow flowers, these two being 

 nearly a half of the whole number ; then follow red, 144 ; 

 purple, 94 ; blue, 87 ; green, 5 1 ; and miscellaneous, 38. 

 Taking each colour by itself, and calculating the per- 

 centages of that colour which has come into flower by each 

 month from April to July, we obtain the following results 

 for the first five classes : — 



Thus of these colours, the blues are, on the average, 

 considerably the earliest in flowering ; then follow in 

 order the whites and the purples, and lastly the yellows 

 and reds. It follows that the plants included in the 

 British flora clearly tend to arrange themselves, as 

 regards the dates of flowering, in the order of the colours 

 of the spectrum, the average earliest being those which 

 are nearest the part of the spectrum where the actinic 

 rays are at the maximum. It will be observed that the 

 differently-coloured varieties of Scilla bifolia are in the 

 same order of flowering of the plants of ihe same colours 

 in the British flora. Accurate observations, continued 

 from year to year, of the exact dates of flowering of 

 different plants, and particularly of differently-coloured 

 varieties of the same species, could not fail to contribute 

 valuable data to the inquiry referring to the influence of 

 the solar rays, in the development of the more important 

 of the vital functions of plants in different seasons. Whilst 

 it is quite true, as has been pointed out by Mr. R. A. 

 Pryor in NATURE (vol. xiii. p. 150), that flowers of all 

 colours bloom in any of the spring or summer months, it 

 is plain that it is only the method of inquiry by averages 

 that can guide us in the search for the law or laws which 

 regulate the seasonal distribution of colour among flowers. 

 It is scarcely necessary to refer to the importance of this 

 question in its possible applications in the rearing of 

 early and late varieties of flowers and fruits. 



Alexander Buchan 



THE WORK OF THE " CHALLENGER " AND 

 THE " VALOROUS'' 



THE Admiralty have just issued Reports on the 

 Soundings and Temperatures taken by the Challenger 

 in the Pacific, and by the Valorous during her voyage 

 out with the Arctic Expedition and home again. 



Captain Thomson's Report is dated from Honolulu, 

 August 8, 1875, and refers to operations in the Inland 

 Sea and to the section from Yokohama to Honolulu. 

 After some days' cruising in the Inland Sea in May, Cap- 

 tain Thomson returned to Yokohama, nothing of interest 

 to the scientific branch having been obtained. The 

 deepest water found in the longitudinal section during 

 the voyage to Honolulu was 3,980 fathoms, whilst that 

 from the turning-point at 156" west longitude down to 

 Honolulu was 3,025 fathoms. The bottom of this section of 

 the North Pacific showed on nearly every occasion red 

 clay, with manganese and pumice-stone in great quan- 

 tities ; the latter greatly increased as the approach to 

 the Sandwich Islands was made. 



Staff- Commander Tizzard makes his preliminary Re- 

 port on the Temperatures of the North Pacific. From 

 Samboangan nineteen soundings and serial temperatures 

 were obtained in the western part of the North Pacific, 

 from which two sections have been constructed, one 

 from the Meangis Islands to the Admiralty Islands, and 

 the other from the latter to Japan. It was found that 

 when the depth exceeded 1,500 fathoms, the thermometer 

 which regulated the bottom temperatures gave the same 

 results as they did at 1,400 fathoms, viz. 34°'4 (corrected). 

 At a little to the southward of Tongatabu, the bottom 



temperature was 32°"9, and as the U.S. officers appear to 

 have obtained colder temperatures at the bottom than any 

 yet obtained by the Challenqer in the North Pacific, 

 Commander Tizzard thinks it probable that the bed of 

 the Pacific is divided into at least three deep basins by 

 ridges of a not greater depth than 1,400 fathoms from the 

 surface. In the southern part of the western portion of 

 the North Pacific the surface-temperature varied from 

 80° to 84°, and that in February and March, considerably 

 higher than any yet registered by the Challenger in the 

 open ocean. 



The Report contains a table of the soundings in the 

 above sections, and four beautifully-constructed sectional 

 charts. The two first show the soundings and isothermal 

 lines from the Meangis to the Admiralty Islands, and 

 between the latter and Japan. The third is intended to 

 illustrate Staff-Commander Tizzard's remarks on the sur- 

 face temperature of the section referred to above ; and 

 the fourth shows the soundings and isothermal lines 

 between Nosema Head, Japan, and the i8oth meridian. 

 One of the most notable features of these charts is the 

 occasional sudden increase in depth ; between Japan and 

 the Admiralty Islands, for example, the bottom sinks at 

 one place all at once from about 2,000 fathoms, on both 

 sides, to a depth of 4,500 fathoms. 



The Valorous on her outward voyage took nineteen 

 soundings in Davis' Straits between 63° 45' and 68° 57' N. 

 lat., the depth being found to vary from 58 to 200 fathoms. 

 The bottom was mostly fine grey sand, mixed with shells, '^ 

 gravel, and stones. On returning south, lower soundings f 

 were obtained along the Greenland coast, with much the \ 

 same results as to bottom. On getting clear of Cape 

 Farewell the course was shaped to cross the Atlantic 

 Ocean between the parallels of 59° and 55^, and to join 1 

 the soundings westward of Ireland obtained in the Po7-- 

 cupine in 1862. The greatest depth obtained was 1,860 

 fathoms in lat. 57° 50' N., and 44° 52' W. long., with a 

 bottom of Globigerina ooze, and a bottom temperature of ! 

 33°*4. In 56° 11' N. lat. and 37° 41' W. long, a depth of 

 1,450 fathoms was obtained, the bottom Globigerina 

 ooze, and next day in lat. 56° i' N., long. 34" 42' W., a 

 submarine ridge of 690 fathoms was sounded on with the 

 same description of bottom. On the day following this, 

 in lat. 55° 58', long. 31° 41' W., the depth increased to 

 1,230 fathoms, mud ; the deep sounding of this day and 

 that of the second day previous being equidistant (103 

 miles) from the intervening shoaler ridge of 690 fathoms. 

 On reaching the 26th meridian of W. long., a westerly 

 gale commenced, which prevented further proceedings. 

 Globigerina ooze, with occasional fine sand and mud, are 

 the main characteristics of this section. Two sectional 

 charts exhibit graphically the data obtained. 



SCIENCE IN GERMANY 

 {From a German Correspondent^ 



MPULUJ, of Fiume, has recently published a de- 

 • scription of a school-apparatus for determining 

 the mechanical equivalent of heat. The apparatus is of 

 very simple construction, and consists of a calorimetrical 

 and a dynamometrical part, which is connected with a 

 rotating arrangement, such as may be found in any 

 physical laboratory. 



The calorimetrical part of the apparatus is formed of two 

 truncated hollow cones of cast iron, fitting the one into 

 the other. The inner one, a, does not quite reach to the 

 bottom of the outer, b, and it projects a little above it. 

 The outer cone, b, can be fixed, coaxially, into the spool 

 of the driving machine. The inner cone contains mer- 

 cury. If, now, the driving machine be set a-going and 

 the inner cone held fast, heat is produced through friction 

 of the touching surfaces of the cones. 



For measurement of the work transformed into heat, 

 the arrangement is as follows :— To the wooden lid, e, of 



