512 



THE POPULAR SCIENCE MONTHLY 



Cayuga ducks. While the birds were still 

 very young, many of them disappeared, and 

 the bodies of several were found with the 

 brains picked out. On watching carefully, 

 a red-headed woodpecker was caught in the 

 act. He killed the tender duckhng with a 

 single blow on the head, and then picked 

 out and ate the brains. 



The " Transactions " of the American 

 Society of Civil Engineers for May contains 

 an article on " Approximate Determination 

 of Stresses in the Eye-Bar Head," by W. H. 

 Burr ; minutes of meetings ; an interesting 

 letter written by (ieneral Philip Scliuyler in 

 1Y99, giving his opinion of a plan proposed 

 by Dr. Brown for supplying this city with 

 water from the Bronx River ; and a list of 

 new books on engineering and technology, 

 besides other matters of interest to engi- 

 neers. 



Mr. McNab, of the Edinburgh Botanical 

 Society, states that the past spring in Scot- 

 land was more backward than any other 

 during the last twenty-eight years. 



Having measured the red blood-cor- 

 puscles of men belonging to fourteen differ- 

 ent races or nationalities, Dr. Richardson, 

 of Philadelphia, found the average diameter 

 to be 1,2^4 of an inch, the maximum diam- 

 eter being 2 7^7-T, and the minimum 



4 u 



The " hard glass " manufactured by 

 Siemens, of Dresden, by means of hydraulic 

 pressure, is said to be stronger than Bastie's 

 glass, in the proportion of five to three. Its 

 fracture, according to the English Mechanic, 

 is fibrous, not crystalline. Besides being 

 stronger, it is also cheaper than Bastie's 

 "tempered" glass; and, unlike the latter, 

 sheets of the Dresden glass can be cut to 

 any size with the diamond. 



The number of blind persons per 100,000 

 of the population of Bavaria is 52 ; of the 

 United States, 52 ; Prussia, 58 ; Belgium, 

 66 ; Switzerland, 11 ; Sweden, 81 ; France, 

 84; Norway, 184. The number of insane, 

 cretins, and idiots, is, in Bavaria, 110 per 

 100,000; in the United States, 160; Scot- 

 land, 185; France, 238; Switzerland, 300; 

 Wiirteniberg, 312; Norway, 340. Of deaf- 

 mutes the United States have 45 per 100,- 

 000; Belgium, 46; Bavaria, 58; France, 

 58 ; Saxony, 60 ; Switzerland, 245. 



Trade, commerce, is usually considered 

 one of the chief influences favoring civiliza- 

 tion ; yet, according to Mr. James Irvine, 

 it has the contrary effect in Africa. Every 

 native is a trader from the day of his birth, 

 and the cultivation of the soil is utterly 

 neglected. The buying and selling of palm- 

 oil, palm-kernels, and a few minor products, 

 give them really all they require, and they 

 cannot be stimulated to further exertion. 



Langeroy, in a communication to the 

 Paris Academy of Sciences, calls attention 

 to the antiseptic properties of bichromate 

 of potassa. According to him, one per cent, 

 of the bichromate in water absolutely pre- 

 vents putrefaction in all animal and vege- 

 table substances. After meat has stood in 

 the solution for a few months it resembles 

 gutta-percha, and medals have been struck 

 li'om it; but it becomes poisonous, and 

 even dogs refuse to eat it. This antiseptic 

 will doubtless be of great use for the pres- 

 ervation of natural-history specimens. 



A SIMPLE and ingenious contrivance for 

 drawing liquids from carboys is described 

 in La Nature. It consists of two tubes 

 passing into the carboy through the stop- 

 per, one of the tubes serving as a siphon, 

 and the other as a means of increasing the 

 air-pressure over the liquid. At its outer 

 extremity the siphon has attached to it a 

 short section of rubber or gutta-percha 

 tube, which may be compressed by a clamp. 

 To fill the siphon, a person blows thiough 

 the short tube, with the clamp relaxed. 

 When sufficient liquid is drawn off, the 

 clamp is allowed to compress the walls of 

 the elastic tube, stopping the flow. 



In a late report on the origin of the 

 skin-disease known as Delhi boil, or, as it 

 has been lately named from its wide distri- 

 bution in the East, Oriental sore, Drs. Lewis 

 and Cunningham reject the view that the 

 affection is attributable to parasitic agency. 

 From extended observations in widely-sep- 

 arated districts they are led to ascribe the 

 disease to the use of well-waters that con- 

 tain a large quantity of salts, and are ex- 

 tremely hard. In Egypt, Asia Minor, and 

 Syria, where the sore prevails, the well- 

 waters are notoriously brackish, agreeing 

 in this with many stations in India, where 

 the disease is also prevalent. 



Dr. C. a. Bressa, deceased in 1835, be- 

 queathed all his property to the Turin Acad- 

 emy of Sciences, the net interest to be given 

 every two years as a prize for the best work 

 done, during the previous four years, in 

 physics, natural history, chemistry, physi- 

 ology, pathology, geology, history, geogra- 

 phy,* or statistics. The fund is now avail- 

 able, and the first award will be made two 

 years hence. The competition will be open 

 to the whole world, and the prize will 

 amount to about |2,500. 



Moles render to the farmer and gardener 

 very considerable service at little or no cost 

 the damage they do being more than com- 

 pensated by the destruction of worms and 

 grubs. When they have eaten all the grubs 

 and worms in a certain place, they emigrate 

 to another, and there repeat their gratui- 

 tous work. 



