FRAGMENTS OF SCIENCE. 



283 



other directions than that on which it is most 

 intently bent. So much for " excess " in 

 bicycling ; for devotion to the machine for it- 

 self ; for " scorching." But of moderate use 

 of the machine, of its employment as an aid 

 to other exercises and recreations, MM. Tissier 

 and Du Pasquier would probably have, cer- 

 tainly ought to have, quite other views. 



Cement as a Fire-proof Covering. Mr. 



J. S. Dobie has recently published the results 

 of a number of tests showing the effect of 

 heat on cements. Tests were made upon 

 pure briquettes and briquettes made up of 

 sand and cement in various proportions. 

 The briquettes were heated in a small assay 

 furnace. The first thing noticed on removal 

 from the furnace was a loss of weight, and 

 the pure cement briquettes almost invariably 

 showed extensive cracks. The loss in weight 

 is due to the driving out of the water of crys- 

 tallization, hardened cement consisting of 

 hydrated crystals of aluminum and calcium 

 silicate. After removal from the furnace, 

 the briquettes were subjected to various 

 tests, and in every case where the water of 

 crystallization had been approximately all 

 driven off the briquettes were unable to 

 resist any load whatever. A high tempera- 

 ture was not necessary to destroy the strength 

 of the cement. The lowest heat which could 

 be generated by the furnace, considerably 

 below red heat, was found to be as destruc- 

 tive as the highest temperature. The con- 

 clusions arrived at by Mr. Dobie were: 1. 

 That while there is no doubt that a covering 

 of Portland cement concrete will afford some 

 protection to a metal column or girder, still 

 there appears to be no doubt that the con- 

 crete itself will be ruined by the action of 

 the fire, and will have to be removed as soon 

 as the fire is subdued. 2. The concrete 

 covering, if heated, will not stand the action 

 of water. In a case of fire, when the hose is 

 turned on, the water strikes the cement cover- 

 ing, probably red hot, and immediately cracks 

 it off, leaving the ironwork bare. 3. In cal- 

 culating for the design of the columns and 

 girders, and especially for floors, no allow- 

 ance should be made for the strength of the 

 concrete, and the cement covering should 

 be considered as so much extra load on the 

 system. 4. That in a fireproof building 

 floors should never be constructed of slabs 



of cement forming short spans or arches 

 from girder to girder, without any support, 

 and that these experiments indicate that the 

 value of concrete as a fire-protecting ma- 

 terial has been greatly overestimated, and 

 that disastrous results may follow, from con- 

 fidence in a building protected with such 

 material. 



Chinese Medicine. The medicine of the 

 Chinese is described by M. Paul d'Enjoy as 

 being more serious, more widely extended, 

 and further removed from superstitious prac- 

 tices than that of the other cognate peoples 

 of the far East. The doctors concoct and 

 sell their remedies, as well as prescribe them, 

 provide themselves with luxurious shops, and 

 use all the tricks of the trade to make their 

 parcels attractive. Many of their remedies 

 are administered in large, badly tasting pills, 

 only slightly mollified in their flavor by lic- 

 orice. These pills are inclosed in capsules 

 of wax as large as pigeons' eggs, which pre- 

 serve the compound from contact with the 

 air, and are broken when the remedy is taken. 

 Special preparations are sent out from the 

 large shops of the principal commercial cen- 

 ters. Among the most popular of the spe- 

 cialties are the little brick-red cholera pills, 

 composed of mangosteen bark and various 

 tropical essences, such as santal, eaglewood, 

 and calumba. Ih^Dcmnhuy'is a medicinal 

 oil which produces excellent efl:ects in head- 

 aches, and generally incases of brain weariness 

 of every kind. It is rubbed on the temples, 

 and is inhaled by strong breathing, after 

 having been rubbed upon the nostrils. Relief 

 is obtained through the cold which its evapo- 

 ration quickly produces. The basis of the 

 preparation is camphor ; and, as a whole, its 

 effect may be compared to that of the head- 

 ache pencils familiar in our drug stores. 

 Chinese medicine is chiefly based on plants, 

 and is taught in books which are often very 

 ancient. In his practice the doctor strictly 

 follows the methods of the master by whom 

 he has been taught. With a very grave 

 face, his eyes protected by large spectacles 

 of thick glass, the old physician feels the 

 pulse of his patient, and never fails to make 

 him show his tongue. Next he examines 

 his eyes, and asks a series of questions, the 

 answers to which will help him out in his 

 diagnosis. Then he writes his prescription 



