SPIRIT OF THE MONTHLIES. 337 



require more strength of team to plougli it than coarse soils. It is 

 evidently silicioiis, and seems to be a fine sediment which was 

 deposited far from land and in a deep sea. 



Analysis — 100 grains gave the following result : 



Water 5-00 



Vegetable matter 9- 50 



Silex 80-21 



Carbonate of lime 1*08 



Phosphate of alumine and lime 0*50 



Protoxide of iron and alumine 3 -62 



99-83 

 The so called marl is really tufa, and is composed of 97 per cent 

 of carbonate of lime. Some parts of it are entirely soluble in warm 

 muriatic acid ; in others, there is a sediment of silicious matter. It 

 is to all intents and purposes a pure carbonate of lime, and may be 

 used for quicklime for mortar, water or agricultural purposes. 



The questions which are put in your letter are not easy to answer, 

 inasmuch as the composition of the soil is not defective. The way 

 to improve it, as it appears to me, is to add coarser materials to it, 

 that is, im|)rove it mechanically — as fragments of old brick, pot- 

 tery, plaster, broken stone, etc. ; also coarse charcoal, bones. A 

 good plan would be to add the broken tufa without burning. I feel 

 that it would be easier to make suggestions on the spot than at a 

 distance ; for, after all, local circumstances must greatly modify the 

 treatment in any given case. E. Emmons. 



[From the same.] 



GESTATION OF COWS. 



Mr. Editor — While living on my farm, I foimd it not only useful, 

 but very necessary, to keep a record of the time my cows were put 

 to the bull, as well as the time of calving. By the means of keep- 

 ing a record, I was enabled to make a calculation on the probable 

 period parturition would lake place, and be prepared for the event, 

 and avoid accidents which might occur when no attention was paid 

 to the subject. 



The experiments and facts which I am about to state, may not 

 be considered of much importance to farmers generally, but to the 

 breeders of cattle, and the inquiring mind, they may, I trust, be 

 interesting ; and some good may possibly result from their publicity. 



Earl Spencer, in a paper comnuinicated to the " Journal of the 

 Royal Agricultural Society of England," says the shortest period 

 of gestation, in which a live calf was produced, was 220 days, and 

 the longest 313 days : difference 93 days. 



M. Tessier, in a memoir read to the Royal Academy of Sciences 

 at Paris, says that in 1131 cows, which he had the opportunity of 



