November io, 1910J 



NATURE 



57 



national importance. An opening meeting of opticians and 

 those interested in optics was called by Mr. J. Aitchison 

 at Anderton's Hotel in Fleet Street on October 17, and 

 an attendance of 300 enthusiastically and unanimously 

 affirmed their approval of the London County Council 

 scheme. This was probably the largest, and certainly the 

 most unanimous, optical meeting ever held in London ; all 

 the speakers emphasised the need for close cooperation 

 between science and industry in the optical more than in 

 most other industries, and the consequent need of the best 

 educational facilities for masters and workmen. It is 

 clearly recognised — not in this country alone — that the 

 British optical industry has made and is making a very 

 great effort to regain lost ground ; such names as Grubb 

 and Hilger show that there is even now British leadership 

 in some fields of optics. With the help of such schemes 

 as that of the London County Council these fields might 

 il be extended. 



THE CRYSTALLOGRAPHY OF 

 H.EMOGLOBINS.^ 



/^ RVSTALS of oxyhaemoglobin differing greatly in 

 ^^ character are figured in every text-book of physi- 

 ology ; but in the absence of specially skilled study by a 

 crystallographer it has always seemed possible hitherto 

 that the differences observed might be dependent on poly- 

 morphism, differences in water of crystallisation, effects 

 of environment, or on chemical change, and that haemo- 

 globin, from whatever source obtained, was essentially one 

 and the same substance. Hiifner's observation that all 

 haemoglobin solutions giving the same extinction coefficients 

 in the spectrophotometer showed the same capacity for 

 oxygen appeared to support such a view, although it 

 could also be interpreted as showing merely, what was 

 already probable on other grounds, that the hsematin por- 

 tion of the molecule was identical in all cases. 



Profs. Reichert and Brown, regarding crystalline 

 character, when interpreted with care and knowledge, as 

 a trustworthy criterion of identity or non-identity, have 

 prepared crystals of oxjhaemoglobin and its near allies 

 from some two hundred species of animals, and subjected 

 them to minute crystallographic analysis. Their observa- 

 tions show beyond doubt that haemoglobin exists in almost 

 innumerable varieties, each of which is more or less charac- 

 teristic of the species from which it was obtained. In 

 view of the ease with which oxyhaemoglobin undergoes 

 chemical change, the demonstrated impossibility of purify- 

 ing it by recrystallisation without the occurrence of such 

 cnange, the effects of admixture with other substances on 

 crystal form, and the difficulties of crystallographic inter- 

 pretation, it is inevitable that some reserve should be felt 

 in accepting all their conclusions in detail, but the main 

 facts presented can hardlv b*' interpreted otherwise than 

 in the way suggested by the authors. 



It is, however, much to be regretted that they have not 

 described the spectroscopic characters of the crystals 

 studied in each case, since the omission of this informa- 

 tion leaves it open to doubt whether the material examined 

 was always wh.at it was taken for. In the absence of 

 spectroscopic evidence, their statement that the blood of 

 the horse, python, and many primates, including man, con- 

 tains in the same individual two different kinds of oxy- 

 haemoglobin, while that of the baboon and some other 

 animals contains as many as three, carries no conviction. 

 Scepticism on this point appears, indeed, to be very much 

 in place in view of the extraordinary statement in the 

 last chapter that " metoxyhaemoglobin," the substance 

 ordinarily known as methaemoglobin, the neutral or acid 

 solptions of which show a four-banded spectrum, becomes 

 converted to oxyhaemoglobin by treatment with ammonia. 

 It is almost impossible to resist the conclusion that the 

 •authors are unfamiliar with the spectrum of alkaline- 

 meth^moglobin. and the suspicion that the crystals 



1 " The Differentiation nnd Specificity of Corresponding Proteins and 

 other Vital Substances in Relation to Biological Classification and Organic 

 Evolution and the Crystallography of Hemoglobins." By Prof. E. T. 

 Reiche't and Prof. A. P. Brown. Pp. xix+338+ 100 plates. (Washington, 

 D.C. : Carnegie Institution, 19C9.) 



NO. 2 141, VOL. 85] 



described as a second kind of oxyhaemoglobin may have 

 consisted of the former substance. 



.Another interesting statement concerning which ampler 

 justification would have been very welcome is that the 

 blood of the shad during the breeding-season, and that o{ 

 the bear during hibernation, is especially rich in " metoxy- 

 haemoglobin." 



The first two chapters deal very completely with the 

 general properties, and distribution in the animal kingdom, 

 of haemoglobin, hsemocyanin, and the colourless respira- 

 tory substances termed achroglobulins ; they contain also 

 some very useful comparisons of the chemical and morpho- 

 logical characters of the blood of different animals, and 

 full references to the literature. The third chapter is 

 devoted to a special consideration of the physical and 

 chemical properties of haemoglobin, and it is no fault of 

 the authors that Barcroft's important work on this sub- 

 ject had not appeared in time for its inclusion. The rest 

 of the monograph contains an admirable critical account 

 of the work of previous investigators, and a full descrip- 

 tion of the methods, results, and conclusions of the 

 authors, illustrated by 600 very successful photomicro- 

 graphs and numerous figures in the text. 



The results obtained are of general biological interest, 

 not only as showing that the differences already proved 

 to exist between the corresponding serum-proteins of 

 different animals are equally manifest between their 

 hzemoglobins, but also as throwing light on phylogenetic 

 relations, since the crystals from closely allied species often 

 exhibit close similarities. They are also of great interest 

 to the crystallographer by reason of the extensive isomor- 

 phous series brought to light, and some important 

 observations on mimetic twinning of crystals. 



PROBLEMS OF WHEAT GROWING. 



71 



HE October number of Science Progress contains an im- 

 portant article on " Wheat-growing and its Present- 

 day Problems," by Dr. E. J. Russell, of the Rothamsted 

 Experimental Station. TTie article is based very largely 

 upon a discussion which took place at the Winnipeg 

 meeting of the British .Association, at a joint meeting of 

 the Botanical, Chemical, and Agricultural Sections. The 

 work of the Rothamsted station has long ago made 

 familiar the main facts in reference to the fertilisation of 

 wheat-fields under normal conditions, but the recent dis- 

 covery of the use of phosphatic manures in order to 

 secure earlier ripening may prove to be an important 

 factor in extending the northern limit of the wheat-belt ; 

 in the same way, it is suggested, the use of late-ripening 

 varieties manured with potassium salts may be of value 

 in extending the southern limit ; phosphates have also^ 

 proved of value in securing rapid root development in the 

 dry soils of Australia, where it is of great importance 

 that the plant should secure access to the subsoil water 

 as quickly as possible. Refeience is also made to the 

 recent experiments of Dr. Saunders and others on the 

 breeding of wheat in order to develop " strength," heavy 

 cropping power, early maturity, and resistance to rust 

 and drought. The work to be done here is very extensive, 

 as different localities demand widely different types, owing 

 both to economic and to physical differences. Even in a 

 given locality the results obtained vary greatly according 

 to the conditions, a " strong " wheat often giving a crop- 

 of weak piebald wheat when grown on newly broken 

 land, whilst on old land the crop may be superior in 

 quality to that used as seed, a difference that is perhaps 

 due to the great decrease in the proportion of water in 

 the older land during the period of growth of the crop. 

 It is pointed out that continuous cropping with wheat 

 appears to break down the fertility of the soil by bacterial 

 changes, which result in disintegrating the nitrogen, rather 

 than by chemical exhaustion; the soil recoveis, however, 

 when planted with clover and similar crops, which act as 

 agents foi the fixation of nitrogen ; as this seems to fit 

 in with the natural development of farming in a new 

 country, the temporary k)ss of fertility is of less import 

 ance than might appear at first sight to be the case. 



