Feb. 3, 1888.] 



SCIENTIFIC NEWS. 



117 



cations of foods and drinks, and continually is the 

 microscope adding new means of detecting adulteration. 

 Microscopy is again useful in noting the characters of 

 fibres used in textile manufactures, and for cordage, 

 paper-making, etc., and so important has this been con- 

 sidered in America that there was formed there in 

 1885 a National Textile Microscopical Association. In 

 agriculture, also, the microscope is of great use. Even 

 as regards the soil it has, by studying micro-organisms, 

 taught much respecting the nitrification of the soil ; but 

 it is especially valuable in noting some of the diseases of 

 plants, such as those caused by the ravages of fungi and 

 minute insects. To the timber merchant, joiner, car- 

 penter, cabinetmaker, and builder, the microscope is of 

 use in noting unhealhty conditions due to fungoid growths, 

 etc. The microscope may be a still further guide to 

 builders in the examination of the mineralogical con- 

 stituents of building stones, and in the same way it may 

 be often serviceable in examining materials used for 

 road-making, paving, etc. Microscopy is also serviceable 

 in practical mineralogy, and capable of detecting mine- 

 ralogical constitution where chemistry fails. 



It is also serviceable to the brewer in noting the purity 

 of the air in the fermenting room, the nature of the water, 

 the quality of the ferment, including the presence or 

 absence of organisms that cause unhealthy fermentation ; 

 and in the same way it is useful to the distiller, and others 

 who have to work with saccharine liquids, such as the 

 sugar refiner. In the mechanical arts microscopes 

 have been employed with advantage in making delicate 

 measurements and in delicate levelling operations ; 

 also in noting causes of difference in the efficiency 

 of tools, consequent on the character of the materials 

 of which they are made. One other use may 

 be mentioned, viz., in connection with the legal profession 

 in the examination in doubtiul cases of handwriting, ink, 

 and paper of documents, etc. In the study of microscopy 

 a knowledge of drawing and the practice of photo-micro- 

 graphy can be of much service, and excellent progress in 

 the latter art has been made of late years, but further 

 developments should be sought for, especially in con- 

 nection with observations with high power objectives. 

 As the microscope is of so much value for practical 

 purposes, it should be studied more than it is in science 

 schools and in connection with trades and industrial 

 occupations. Even in ordinary school teaching it might 

 be made available for exciting greater interest in the 

 studies than is often given now, and in giving a training 

 in habits of thorough and careful investigation ; but in 

 trade and technical schools a training in its use should 

 form an important part of the curriculum. In many 

 such schools on the continent practice with the microscope 

 is insisted on, and the value of such study has been 

 testified to, not only by the professors under whose 

 auspices the instruction has been given, but by a large 

 number of manufacturers and others in whose service 

 the students have subsequently worked. 



SOCIETY OF ARTS. 

 At the meeting held on the iSth ult.. Sir Richard 

 Webster, M.P., presiding, Mr. John Leighton read a 

 paper, on "A Proposal for a Postal Ballot." Mr. J. 

 Withers, one on "Ballot Voting Apparatus," and Mr. J. 

 Iroray, a communication entitled "Apparatus for Voting 

 by Ballot." 



PHYSICAL SOCIETY OF GLASGOW UNIVERSITY. 

 At the meeting held on the 13th inst. Mr. Bunji Mano 

 read a paper on the " Testing of Lubricants," in which 

 he called special attention to the fact that in estimating 

 the value to engineers of various lubricants, their con- 

 stancy of action in keeping a cool surface with a low 

 co-efficient of friction and a high temperature of decom- 

 position was of much more importance than their money 

 value. 



ROYAL BOTANIC SOCIETY. 

 At a meeting of this Society, held on the 14th ult.. Dr. 

 Prior exhibited specimens of the sweet acorn called 

 Bellotas, of which great quantities are brought into the 

 markets of Northern Africa and Spain during the 

 autumn months, and are eaten raw, boiled or roasted, or 

 made into bread by the inhabitants. 



»^S»t^i^5<f-» — 



CORRESPONDENCE. 



The Editor does not hold himself responsible for opinions expressed 

 by his correspondents, nor can he take notice of anonymous com- 

 munications. All letters must be accompanied by the name and 

 address of the writer, not necessarily for publication, but as a 

 guarantee of good faith. 



THE FOG-BOW. 

 Professor Tyndall has had the good fortune to witness a fog 

 or mist-bow in Hampshire, and in his letter to the Times on the 

 subject he mentions the rarity of its occurrence. Itwill doubtless 

 be within the recollection of those members of the British 

 Association who returned from Canada on the s.s. Pai isian that 

 a very well-defined and complete fog-bow was seen about 1 1 

 a.m. in theGulf of St. Lawrence, during a white fog, which was 

 so dense that the sea was invisible a few yards ahead of the 

 steamer. J. Emerso.x Dowson. 



INSTINCTIVE FEAR. 

 Can any of your readers explain why some animals in times ot 

 imminent danger are said to feign death ? Death is an unknown 

 state to each living creature ; how then can they feign it ? Many 

 facts are given showing the gradual acquisition of instinctive 

 fear, or hereditary dread of man during the period of human 

 observation ; yet acute observers, like Charles Darwin, assert 

 that in no one case has the attitude in which the animal feigned 

 death resembled that in which the animal really died. Is 

 the so-called instinct, then — at least in insects — merely an 

 instinct to remain motionless in the presence of danger, and 

 thus elude the notice of man 'i or is there anything more, and 

 what is that more ? Observer. 



SERPENT POISONS. 

 Your correspondent " Surinamensis " is correctly informed 

 respecting tlie relation between the bites of venomous serpents 

 and tropical fevers. Persons inoculated with diluted venom 

 of the rattlesnake develop symptoms closely resembling those 

 of yellow fever, and the venom m this form is largely used by 

 the Homoeopathic School both as a curative and prophylactic 

 agent in the treatment of this fever. 



Percy Wilds, M.D. 



MICRO-ORGANISMS. 



I notice in your first weekly number tliat " Sigismund "^ 

 writes of the above: — "These tiny beings will very probably 

 play in the future no unimportant part in the manufacture of 

 organic products." That this, indeed, is extremely probable 

 was pointed out by myself in the early part of last year, in the 

 course of a discussion upon " Micro-organisms," at the Society 

 of Arts. 



Even at the present time the bulk of the alcohol, and all the 

 indigo produced mdustrially, is really due to the vital develop- 



