208 



HARDWICK&S SCIENCE-GOSSIP. 



concentrated preparations and tabloids retained their 

 efficiency throughout the whole journey, and were of 

 the utmost value by reason of their efficiency and 

 portability," 



My readers will doubtless remember that in March, 

 1888, I contributed an article to this magazine on 

 Benzoyl Sulphonic Imide, the now familiar 

 Saccharin, in which I described the tabloids of 

 that potent chemical product, which I had had 

 a recent opportunity of testing and seeing made ; 

 during the past two or three years tabloids of four 

 hundred sorts have made their appearance in the 

 chemist's shop, and this marks a gigantic advance 

 in scientific dispensing. 



Mr. Thomas Stevens, the correspondent of the 

 "New York World," in a lively work entitled 

 " Scouting for Stanley," gives some bright pictures 

 of life in the Dark Continent. Mr. Stevens was the 

 first person to reach the famous explorer when he 

 was returning to civilisation, and to take him news 

 from the land of the white men. He says : — 

 "Perfect health for the average European is not 

 to be hoped for in Equatorial Africa. From 

 Mombasa inland to Kilimanjaro, however, and on 

 the elevated plains over which the author hunted and 

 scouted for news of Stanley, one need fear nothing 

 worse than what the pioneer settlers of America had 

 to contend with in the way of fevers and agues. It 

 was always something of a puzzle to Dr. Abbott and 

 myself why a robust man should not escape sickness 

 altogether. We lived well. Every day we disposed 

 of a saddle of venison ; ringing the changes from day 

 to day on hartebeest, wildebeest, mpalla, zebra, 

 waterbuck, eland, with now and then a rhinoceros 

 roast or steak, and other variations. About once 

 a month, however, we came in for a touch of fever. 

 Burroughs, Wellcome & Co., the American chemists 

 of Snow Hill, London, had kindly fitted out the 

 expedition with a chest of their excellent tabloids. 

 These were always immediately effective in breaking 

 up the fever as well as in curing the many ailments 

 of the men. One cannot speak too highly of the 

 medicines put up in the compact form of tabloids by 

 this firm. Their extreme portability is not the least 

 of their recommendations to the African traveller. 

 Stanley, in recommending these medicines in his 

 'Congo, and the Founding of its Free State,' has 

 earned the gratitude of every one who goes to a 

 tropical country. Their saccharin tabloids are 

 especially valuable, as they have three hundred 

 times the sweetening power of sugar." 



To come to another part of the subject, Mr. Parke, 

 in his remarks to the British Medical Association, 

 drew pointed attention to the greater vitality and 

 physical and mental vigour of his European com- 

 panions ; they were generally picked men, and so 

 far above the average of their countrymen ; at the 

 same time they seem to have suffered little from 

 disease and to have absolutely escaped death, except 



two, who were killed, while the native Africans 

 suffered frightfully, and one third perished ; they 

 had no stamina, no capacity to resist disease and 

 exposure ; another proof that modern civilisation 

 does not unfit men for the severest toil and the 

 greatest risks. 



My visit to the British Medical Association gather- 

 ing has left many permanent impressions on my 

 mind, amongst these the appearance of Mr. Parke, 

 and seeing the famous medicine chest are not the 

 least pleasant. 



A Quondam Medical Editor. 



CONCERNING MANURES. 

 By F. Barker Cooke, F.C.S., F.I.C. 



PLANTS derive their carbon from the air in the 

 form of carbonic acid gas, but all their other 

 constituents by osmotic action from the soil in which 

 they grow. Under favourable conditions, such as 

 light, moisture, warmth, etc., they grow luxuriantly, 

 produce seed, which is scattered around them, and 

 then, if annuals or biennials, die. New plants 

 spring from the seeds, drawing their nourishment 

 from the soil, whilst the old ones rot on the surface, 

 and thus return to the ground all the constituents 

 before drawn from it. If this be allowed to go on 

 year after year the soil will become richer and richer 

 in plant-food, which is thus drawn from the sub-soil 

 to be stored on the surface. But if, on the contrary, 

 the crop, such as wheat, be yearly cut down and 

 carried away, the soil is yearly deprived of its plant- 

 food, and thus becomes gradually exhausted. It is, 

 therefore, necessary to replace those substances thus 

 abstracted, and this is done by means of manures. 



But soils vary very much in composition : thus, in 

 one field lime may be plentiful, but from another 

 practically absent ; and hence manures may be 

 defined as any substance applied to the soil, not only 

 to replace those absorbed by a previous crop, but 

 also to supply any natural deficiency in the soil. 



The roots of plants also materially affect the 

 character and fertility of soils. Thus barley with 

 very short roots obtains its food from the surface-soil 

 and does not affect the sub-soil, whence clover with 

 very long roots draws its supply. In the latter case 

 the roots open the soil, and thus assist its oxidation, 

 and further, form a fruitful source of nitrogen from 

 their decomposition in the land after the crop has 

 been cut. A farmer takes advantage of all this, and 

 would grow a crop of clover before that of wheat, 

 which has a special attraction for nitrogen. This is 

 what is meant by the rotation of crops. 



But a further circumstance must influence this, 

 viz., that different kinds of plants do not require the 

 same plant-food in the same proportion. Thus, 

 according to Professor Wrightson, "turnips remove 

 five times, beans three times, and oats twice as much 



