August 14, 1884] 



NA TURE 



367 



In order to render the instrument perfectly reliable, all that 

 is necessary is that the current of water should be always 

 perfectly uniform, and this is easily attained by fixing the 

 size of the outlet once for all, and also the level of water 

 in the tank. So arranged, the pyrometer works with great 

 regularity, indicating the least variations of temperature, 

 requiring no sort of attention, and never suffering injury 

 under the most intense heat ; in fact the tube, when with- 

 drawn from the furnace, is found to be merely warm. If 

 there is any risk of the instrument getting broken from 

 fall of materials or other causes, it may be fitted with an 

 ingenious self-acting apparatus shutting off the supply. 

 For this purpose the water which has passed the ther- 

 mometer is made to fall into a funnel hung on the longer 

 arm of a balanced lever. With an ordinary flow the 

 water stands at a certain height in the funnel, and, while 

 this is so, the lever remains balanced ; but if from any 

 accident the flow is diminished, the level of the water 

 in the funnel descends, the other arm of the lever falls, 

 and in doing so releases two springs, one of which in 

 flying up rings a bell, and the other by detaching a coun- 

 terweight closes a cock and stops the supply of water 

 altogether. 



It will be seen that these instruments are not adapted 

 for shifting about from place to place in order to observe 

 different temperatures, but rather for following the varia- 

 tions of temperature at one and the same place. For 

 many purposes this is of great importance. They have 

 been used with great success in porcelain furnaces, both 

 at the famous manufactories at Sevres and at another 

 porcelain works in Limoges. From both these establish- 

 ments very favourable reports as to their working have 

 been received. W. R. Browne 



THE AGRICULTURAL INSTITUTE OF 

 BE A UVAIS 



\KJ E have already referred to the interesting collection 

 ** exhibited in the Technical School at the Health 

 Exhibition by the Brothers of the Christian Schools. 

 One of the most instructive of their specimen museums is 

 that from their Agricultural Institute at Beauvais. 



This Institute was founded in 1855, the late Prince 

 Consort being one of its first patrons. Recently the 

 Agronomical Society of France have extended to it an 

 encouraging hand. 



Candidates for admission to the school must be at least 

 sixteen years of age, and must give evidence, either by 

 certificates obtained or by a preliminary examination, of 

 their having successfully studied the recognised branches 

 of a good modern education. The course of instruction 

 extends over a period of three years, and is intended to 

 prepare young men to manage and develop estates and 

 direct all farming operations. Special provision is made, 

 in the third year, for those who wish to qualify them- 

 selves for agricultural professorships. The syllabus of 

 subjects is framed by a Board appointed by the prefect 

 of the departement, and consists of the Director and 

 Professors of the Institute, of the Professor of Agriculture, 

 and the Veterinary Surgeon of the departement, as also 

 of three other members. 



The subjects for the first year are : French language, 

 book-keeping and commercial subjects, elementary- algebra 

 and geometry, the fundamental principles of agriculture, 

 rural law and engineering, general zoology, arboriculture, 

 horticulture, physics, chemistry, and linear drawing. 



In the second year the students follow more advanced 

 courses of agriculture, zoology, botany, entomology, 

 geology, surveying, levelling, physics, general and ana- 

 lytical chemistry, rural law and engineering, linear draw- 

 ing, arboriculture, and horticulture. 



The instruction for the last year comprises agriculture, 

 arboriculture, horticulture, analytical chemistry, botany, 



geology, entomology, applied mathematics and me- 

 chanics, and architectural drawing. 



Science teaching, to be of any use, must be prac- 

 tical ; the authorities of the Agricultural Institute, fully 

 convinced of this, attach great importance to labora- 

 tory and field work. In the physical laboratory, the 

 work is exclusively of a demonstrational kind, the 

 students not being required to test the accuracy of 

 their knowledge or their familiarity with instruments 

 by the actual and precise measurement of physical con- 

 stants. Nor do such measurements appear necessary 

 for the object in view. It is, of course, quite different 

 with chemistry, where skill in quantitative analysis is of 

 the highest value to any one who intends to direct the 

 agricultural interests of a district. The students are con- 

 sequently trained with much care in those branches of 

 analytical chemistry which bear directly upon the science 

 of agriculture. The study of botany, geology, and ento- 

 mology is encouraged and stimulated by frequent excur- 

 sions to the neighbouring country, the specimens brought 

 back being compared, classified, and minutely described 

 in appropriate language. 



The school has also a model farm of 325 acres, in 

 which the principal operations of farming are extensively 

 carried on. The students visit this farm at stated hours 

 every week ; they are familiarised with the chief imple- 

 ments and agricultural appliances, and are required to 

 take part in all the regular work that may be going on. 



The Professors have set aside a number of acres for 

 experimenting upon the conditions most favourable to the 

 growth of the principal cereals. These comparative 

 studies are carried out with the assistance of the students 

 mainly for the purpose of showing them how to practically 

 initiate a scientific investigation of an agricultural nature. 

 The results of these studies are fully described in the 

 Annates de I'lnstitut agricole, a yearly publication of 

 considerable merit. A valuable synopsis of the results 

 obtained by the Director of the School, Brother Eugene, 

 will be found in the Educational Section of the Inter- 

 national Health Exhibition, Room 5. 



From a recent report, we find that there have been, this 

 year, under cultivation no less than sixty-five kinds of 

 wheat, twenty of oats, ten of barley, eight of rye, besides 

 fields of potatoes, beetroot, cabbage, &c. There are also 

 pasture lands for sheep and cows, and a well-stocked 

 poultry yard. 



At the end of each year the students are put through 

 a practical examination, when they are expected to give 

 satisfactory evidence of their competency to deal with the 

 general working of the farm. It is also required by the 

 programme of the Institute that the students shall visit 

 exhibitions of an agricultural character which may be 

 held in the vicinity, and attend with their Professors 

 certain markets and sales of live stock. 



The attention of the students is maintained and quick- 

 ened by requiring them to write, with considerable care, 

 notes of all their courses, as well as detailed reports of 

 what they may have seen in their visits or met with in 

 their excursions. Several volumes of these reports, notes, 

 and theses, together with typical herbaria, specimens of 

 grain and seeds, may be seen in the Exhibition, Room 5. 



Besides superintending the museum and giving instruc- 

 tion in the laboratories, the Brothers teach drawing, 

 physics, chemistry, botany, geology, zoology, &c, leaving 

 such subjects as rural jurisprudence and engineering, 

 agriculture, and the like to other eminent professors. 



IS SALPA AN EXAMPLE OF ALTERNATION 



OF GENERATIONS? 



T"HE chances against the accidental discovery of a 



-*■ great natural law are so great that we cannot feel 



surprise that naturalists are slow to believe that Salpa, 



