5o8 



NA TURE 



[March 28, 1895 



and branches " Thus a single tree may rapidly march 

 away from the original planting-point until its outer verge 

 may be an indefinite distance from its place of origin." 

 This method of growth enables the grove to resist even 

 fairly strong waves, and facilitates the accumulation of 

 organic debris and inorganic sediment. 



Again, there are some striking remarks on the accumu- 

 lation of molluscs, especially bivalves. Prof. A. Agassiz 

 has already called attention to this process on the great 

 Florida plateau, and Prof. Shaler particularly mentions 

 the special importance of the oyster as a rock builder 

 along the whole coast from New York southwards. 



" In its maximum development " he says, '' the larger 

 part of the shallow bottom inside the ocean beach is 

 occupied by beds of these shells. So crowded are these 

 forms, that they push their growth above the level of low- 

 tide mark, and in the region where the mangroves 

 abound they cluster on the roots of the trees to such 

 numbers as often to hide them from view. . . . Between 

 Charleston, South Carolina, and liiscayne Bay, Florida, 

 there is an aggregate area of nearly a thousand square 

 miles which, when the shore assumed its present elevation, 

 was occupied by tolerably deep water that has now 

 become filled to near the level of high water, by sediments 

 composed in large part of oyster-shells." 



In fine, these three essays contain not a few 

 interesting and suggestive passages. The illustrations 

 often are very good. 



THE CHEMISTRY OF COD- LIVER OIL. 

 Cod-liver Oil and Chemistry. By F. Peckel M oiler, 

 Ph.D. (London: Peter Miiller, 43 Snow Hill, E.C., 

 and at Christiania, Norway, 1895.) 



THIS book is divided into two parts — the title of 

 part i. is " Cod-liver Oil " ; the title of part ii. 

 is "The Law of Atomic Linking, diagrammatically 

 illustrated," and the heading of the first chapter of the 

 second part is " Chemistry." There is a separate 

 preface to each part, and, though bound together in one 

 volume, each forms an independent treatise, and is 

 separately paged. One hundred and eleven pages are 

 devoted to " codliver oil," and rather more than five 

 hundred to " chemistry." 



In the preface to the first part the author gives two 

 reasons for the publication of ihe work : (r) to deal with 

 .all m itters connected with cod-liver oil, and especially 

 with those likely to be of interest to members of the 

 medical profession ; and (2) to give the results of the 

 investigations lately undertaken by Mr. Heyerdahl, which 

 " throw the first and only true light on that mystery, 

 the real nature of the oil." 



The first and second chapters give an interesting 

 account of Norway, which is styled " the land of the mid- 

 night sun and codliver oil"; its people, past and 

 present ; its social customs ; the Gothenburg system in 

 every town ; its land question ; its fisheries, fishermen, 

 and fishing boats, their tackle and bait ; its tourist 

 visitors, and its " oldest established visitor," the cod-fish. 



The next chapter is on " cod-liver oil,' and the 

 reader is instructed, as pleasantly as in the preceding 

 chapters, in the ancient and modern methods of pre- 

 paring the oil for use. The older method, it appears, 

 was in use until so late as the year 1853, when a 

 NO. 1326, VOL 51] 



great improvement was effected by the introduction of 

 the steam process of extraction, by which means the 

 pure oil only is obtained from the livers, instead of oil 

 mixed with a great number of decomposition product?. 

 This steam process was a great advance. The resulting 

 oil had lost much of its objectionable taste and smell, 

 but it still retained one very bad characteristic — it was 

 still very apt to give rise to nauseous eructations. 

 Unwelcome flavours continued to assert themselves after 

 a dose of such oil, not once only but again and again, 

 till, as the author says, the unhappy recipient was 

 tempted to say, " life is not worth living if it is to be 

 only at the cost of taking cod-liver oil." Hence the 

 host of attempts that have been from time to time made 

 to treat the oil so as to abolish these disagreeable 

 properties. These are dealt with in the chapter called 

 " Pharmaceutical Annotations," and some forty different 

 ways of disguising or improving the oil are described 

 in detail — the ingredients for mixing with the nauseous 

 article including such diverse things as beer, iron- 

 water, peppermint oil, coffee, eucalyptus oil, wood-tar, 

 ammonia, ketchup, celery-seed infusion, vinegar, 

 iodoform, saccharin, acetic ether, &c. ; and, besides 

 all these, every conceivable form of emulsion seems 

 to have been tried. It will be welcome news to 

 many that, in Dr. Moller's opinion, all these elaborate 

 preparations are now quite uncalled for, and that 

 Heyerdahl's investigations have at length led to the 

 possibility of an oil being produced more curative 

 than the old oil, and quite free from nauseating powers. 

 These researches are fully described in a separate chapter, 

 and are considered to have revealed the presence in 

 the oil of two hitherto unknown glycerides, which have 

 been named, respectively, thcrapin and jccolein. They 

 are both exceedingly unstable compounds, and easily 

 become oxidised, and these oxidation products are 

 believed to be the real cause of the too well-known 

 unpleasant after-effects of the drug. As a result of these 

 discoveries an apparatus has now been devised by which 

 cod-liver oil can be produced on a large scale without 

 even the slightest oxidation taking place. Air is 

 excluded from the beginning to the end of the operation, 

 the process being conducted in a current of carbonic 

 acid from the moment the livers enter the apparatus 

 until the oil obtained from them is safe within the 

 bottles. 



The chapter giving a synopsis of the chief researches 

 on the oil since 1822 is very complete, and will no doubt 

 prove of great interest to medical men and pharmacists. 



The conclusion arrived at as to the therapeutic agent 

 in cod-liver oil is that " it is the oil itself," and that its 

 remarkable power as a nutritive food is the cause of its 

 medicmal elticacy, and not any special active principle 

 contained in it. This opinion is in agreement with tl1.1l 

 of the late Prof. J. Hughes Bennett, of Kdinburgh, who 

 published, in 1841, a pamphlet on cod-liver oil, which had 

 much to do with the general introduction of the oil as a 

 medicine into this country. It is one of the omissions 

 in the present volume that no reference is made to the 

 work of Dr. Bennett in this direction. 



The object of the second part of this work, as set 

 forth in the pref.ice, is mainly to bring the facts of 

 organic chemistry, freed from unnecessary difficulties, 



