December 9, 1915] 



NATURE 



399 



African elephant of known height showingf that 

 it probably stood 15 ft, at the highest part of 

 the back. Thus the humerus is 4 ft. 4 in. in 

 length, while the humerus of an African elephant 

 said to have been 11 ft. 4 in. high is a foot less. 

 Ihe beds in which the bones were found consist 

 of a series of sandy clays and tough clay with 

 numerous flints, much race and ironstone. These 

 were deposited against the side of a slope composed 

 of chalk below and Thanet sands above (Fig. i). 

 Their exact age is doubtful, but probably they 

 are nearly contemporary with the bone-bearing 

 beds of Grays or perhaps earlier. The molar 

 teeth seem to have belonged to an early form of 

 Elephas antiquus, and closely similar to some dis- 

 covered at Mosbach. 



During the excavation the military authori- 

 ties gave every possible assistance, and with- 

 out their help the work would have been much 

 more difficult, if not impossible. The speci- 

 men has been presented to the British 

 Museum by the War Department. The bones 

 are now being freed from their wrappings 

 and hardened, but it will be some time before 

 they will be ready for exhibition. 



Chas. W. Andrews. 



BACTERISED PEAT AS A FERTILISERA 

 ''T^HE horticultural world has been interested 

 -■- for some years in Prof. Bottomley's 

 attempt to prepare a new fertiliser from peat. 

 The reasons for that interest are manifest : 

 farmyard manure is constantly increasing in 

 price and decreasing in amount ; and arti- 

 ficial fertilisers, excellent auxiliaries though 

 they be, cannot impart to the soil those 

 physical properties without which plants do 

 not thrive. 



The market grower, accustomed to raise 

 heavy crops on land treated with enormous 

 dressings of manure — ^100 tons or more to 

 the acre — is only too anxious to discover 

 other and less costly means of enriching his 

 soil ; and even the general public — if we may 

 judge from the attention which is being 

 bestowed in the daily Press on Prof. Bottom- 

 ley's discoveries — is alive to the importance 

 of increasing the fertility of the land. Hence 

 the spirit of the soil manifests itself oppor- 

 tunely in conjunction with the spirit of the 

 times. It purports to reveal the mystery of the 

 mode of action of bacterised peat — the fertiliser 

 which Prof. Bottomley prepares from peat-moss 

 litter and from certain kinds of raw peat. 



Mr. Knox, the author of this volume, has done 

 his work well. He tells his story graphically yet 

 simply, although in chapter ix., entitled "Ele- 

 mentary Conceptions of Chemistry, etc.," he 

 showers a rain of atomic bombs on the reader 

 with such effect that that much-enduring person 

 will doubtless seek cover in the next chapter. 

 Briefly, this is the story that Mr. Knox has to 



tell. Certain aerobic bacteria possess the power 

 of liberating from peat large quantities of soluble 

 hu^ates. These soluble humates are in them- 

 selves of service to plants as sources of food. 

 They serve, moreover, as a culture-medium in 

 which nitrogen-fixing bacteria — azobacter chroo- 

 coccum, etc. — multiply rapidly. H'ence by adding 

 cultures of nitrogen-fixers to sterilised humated 

 peat, the amount of nitrogen in the latter is 

 increased. 



It was to this large nitrogen content that Prof. 

 Bottomley originally attributed the fertilising 

 powers of bacterised peat. Tests carried out at 

 Kew on many different kinds of greenhouse 

 plants — lilies (see Fig. i), cyclamen, coleus (see 



1 "The Spirit of th« Soil." 

 Constable and Co., Ltd., igis.) 



G. D. Knox. Pp. xiii-J-2+2. (L 

 rice 7.S f>d. net. 



NO. 



2406, VOL. 96] 



. I. — The left of the two lilies shown in the illustration was grown in humogen 

 and ordinary .soil, while that on the right was grown in a complete food com- 

 post. The average number of blooms on the batch (48 size pots) was six as 

 against four, and it should be noted that this is the common effect of humogen 

 treatment on bulbs. (The Royal Gardens, Kew). From " The Spirit of the 

 Soil." 



Fig. 2), primulas, etc. — indicate in most striking 

 manner that the addition of bacterised peat to a 

 potting compost brings about a great increase of 

 growth and vigour. The amount of bacterised 

 peat (or humogen, as it is sometimes and some- 

 what inconsequently called) which produces these 

 results is about lo per cent, of the total compost. 

 Anyone who takes the trouble to reckon what 

 10 per cent, means in tons per acre will recognise 

 that, unless far smaller dressings of bacterised 

 peat may be used, this fertiliser cannot be applied 

 with success to field crops ; and indeed, in certain 

 field experiments which we have witnessed the 

 addition of dressings of bacterised peat at the rate 



