SCIENTIFIC NEV\^S. 



Quiy 1st, 1887. 



logia Iconica," Sowerby's and Adam's works on shells, Sir 

 John G. Dalyel's " Rare and Remarkable Animals of 

 Scotland," and Nehemiah Grew's " Anatomy of Plants." 

 The natural history specimens consist of about 7,000 species 

 of shells and sixty glass models of invertebrate animals, 

 which, together with the other collections in the college 

 will make this section of the museum one of the most 

 complete in the country. The museum has also recently been 

 enriched by donations from several well-known IVIanchester 

 gentlemen, of specimens from the great find of fossil 

 hippopotami at Barrington, near Cambridge ; and by the 

 gift of the large fossil stigmaria found in the carboniferous 

 rocks at Clayton. 



Measuring the Bulk of Solids. — The following descrip- 

 tion of a simple apparatus for measuring the bulk of a small 

 solid body, without immersing it in water, and without 

 weighing it, is taken from the Chroniqiic Indiistrielle. The 

 instrument consists of a graduated glass tube, which is closed 

 at one end with a rubber stopper, and at the other end 

 with a metal cap, capable of being screwed on or off The 

 metal cap is made flat and broad, so that it can serve as a 

 stand for the tube when in an upright position. Sand is 

 put into the tube until it reaches the zero on the graduated 

 scale, and the rubber stopper is inserted. The tube is then 

 turned upside down, the metal cap is unscrewed, and the 

 object to be measured is inserted. The cap is screwed on 

 again, and the tube is replaced in its upright position. 

 The level of the sand in the tube should then be noted, 

 and the volume sought for will be seen on the graduated 

 scale. 



A Meteorite in Coal. — At a meeting of geologists at 

 Bonn, Dr. Gurlt recently described a fossil meteorite 

 found in a block of tertiary coal, and now in the 

 Salzburg Museum. It had been examined by several 

 specialists, who assigned different origins to it. After 

 careful examination Dr. Gurlt had come to the conclu- 

 sion that it was a meteorite. In form the mass is almost 

 a cube, two opposite faces being rounded, and the four 

 others being made smaller by these roundings. ' A deep 

 incision runs all round the cube. The faces of the incision 

 bear such characteristic traces of meteoric iron as to ex- 

 clude the notion of the mass being the work of man. The 

 iron is covered with a thin layer of oxide, it is as hard 

 as steel, and contains, as is generally the case, besides 

 carbon, a small quantity of nickel. It resembles the cele- 

 brated meteoric masses of Saint Catherine, in Brazil, and 

 Braunau, in Bohemia, discovered in 1847, but it is much 

 older and belongs to the tertiary period. 



Growth of the Heart. — According to Dr. Benecke, of 

 Marburg, the increase in the growth of the human heart is 

 greatest and most rapid during the first and second years 

 of life, its bulk at the end of the second year being exactly 

 double what it was at birth ; between the second and 

 seventh years it is again almost doubled. A slower rate of 

 growth then sets in, until about the fifteenth year, the 

 augmentation of volume during the intervening seven or 

 eight years being only about two-thirds. In the period of 

 maturity which then approaches the growth of the heart 

 again makes progress, the increase keeping pace with the 

 advance toward maturity of the other portions of the system. 

 After the fifteenth year, up to the fiftieth, the annual 

 growth is about -061 of a cubic inch, the increase ceasing 

 with the fiftieth year, a shght diminution then ensuing. In 

 childhood the male and female hearts are alike ; after 

 maturity the male heart develops more than the female, 

 and the difierence thus established is said to be maintained 

 throughout the remainder of life. 



Effect of Freezing on Bacteria. — Some important 

 experiments have recently been made by Dr. T. Mitchell 



Prudden, of New York, on the effect of freezing on bacteria. 

 In the case of Bacillus prodigiosus, there were 6,300 bacteria 

 in a cubic centimetre of water before freezing ; after being 

 frozen 4 days, 2,970 ; after 37 days, 22 ; and none after 51 

 days. Of the Staphylococcus pyogenes aureus, there were 

 a countless number before freezing; after 18 days of freez- 

 ing, 224,598 ; after 54 days, 34,320 ; and after 66 days, 

 49,280. Of the Typlioid-fever Bacillus, the numbers were 

 innumerable before freezing ; 1,019,403 after being frozen 

 II days; 336,457 after 27 days; 89,796 after 42 days; and 

 7,348 after 103 days. These results show that certain 

 bacteria have a remarkable power of resisting the tempera- 

 ture at which water freezes ; and Dr. Prudden recommends 

 that the New York State Board of Health, or other authority, 

 should have power to determine which, if any, of the 

 sources of ice-supply are so situated as to imperil the health 

 of persons consuming the ice. 



Sensitiveness of the Sense of Smell. — From Liebig's 

 Annalen, we learn that Drs. Fischer and Penzoldt have made 

 a series of experiments upon the sensitiveness of the sense 

 of smell. They used mercaptan and chlorphenol as their 

 odoriferous substances and experimented in a room of 230 

 cubic metres capacity. A gramme of the substance was dis- 

 solved in a litre of alcohol ; 5 c.c. of the solution were again 

 diluted to a known volume, and from i to 3 c.c. of the latter 

 solution were measured out into a flask from which a fine 

 jet could be directed by the experimenter to all parts of the 

 room, the air of which was subsequently agitated by the 

 waving of a flag. At a given signal a second experimenter 

 stepped into the room, and took his olfactory oljservation, 

 which was checked by the independent observation of a third 

 person. The result arrived at was that our olfactory nerves 

 are capable of detecting the -^^ part of a milligramme 

 of chlorophenol, and the 4600^0 par' of a milligramme 

 of mercaptan. 



The Hydrophone. — From La Lunncre Electrique we learn 

 that Mr. A. Pares, of Altona, (Germany), has devised an 

 extremely ingenious apparatus for detecting leakage in 

 water mains. A rod, made of a substance that conducts 

 sound well, is held in a vertical position by a tripod, and to 

 its upper extremity is attached a metallic box containing a 

 microphone. The apparatus is completed by a regenera- 

 tive dry pile, a telephone receiver, and a pear-shaped 

 contact-maker that permits of leaving the pile circuit open, 

 and of closing it only at the moment of observation. On 

 moving the rod over the water-pipe, any leak can be dis- 

 tinctly heard by the ear. It appears that the sensitiveness 

 of the apparatus is such that the slightest leak in the pipes 

 inside of a house can be ascertained from the street. 

 When the observation is made in a place where there is 

 much noise, it is well to use two telephone receivers, or, if 

 but one be used, to close one ear by means of a small 

 device which Mr. Pares calls an antiphone, and which forms 

 one of the adjuncts of the apparatus. The microphone is 

 so constructed that it can be fixed directly to a water pipe. 



Salicylic Acid in Food. — The use of salicylic acid 

 to prevent the fermentation of articles of food and drink 

 especially susceptible to this change during storage or 

 carriage has much increased of late years. Salicylic 

 acid, however, and its salts tend to retard the action 

 of the digestive fluids, and they have been supposed 

 to act deleteriously on persons affected with weak digestion 

 or renal troubles. In fact, the compounds have come to 

 be viewed with gravest suspicion, and their use has been 

 interdicted by many officials of boards of health. The 

 French Government has recently had this matter carefully 

 investigated through the Academy of Medicine. Their con- 

 clusions show that salicylic acid, in small doses, is probably 

 harmless, but in larger quantities acts injuriously. As the 



