43 



THE POPULAR SCIENCE MONTHLY. 



tion. From the search for supernatural 

 means of driving away the evil spirits sup- 

 posed to be working harm to the child have 

 arisen very curious and wide-spread doc- 

 trines which are of great value in the history 

 of customs. The little being who has come 

 into the world is not always believed to be 

 pure, and to have a clear right to existence. 

 Many peoples regard it as " unclean " and 

 not to be touched for a certain time. Others 

 require it to be expressly recognized by the 

 father ; and some give the parents a right 

 to expose or kill it immediately. Among 

 most people it is considered essential to per- 

 form some kind of ceremony for formally 

 adopting the child into the family and so- 

 ciety. Such ceremonies are generally dietetic, 

 or relate to washing and bathing, anoint- 

 ing the skin, giving the first food, circum- 

 cision, putting on clothing, or cutting the 

 hair, and are observed as important mys- 

 teries favorable to bodily endurance and 

 mental vigor. Here we approach the tran- 

 sition from the instinctive hygiene of popu- 

 lar customs to religious ceremonies. Sur- 

 vivals of the notions here pointed to are 

 traced by Herr Ploss among popular cus- 

 toms that have not yet died out in the more 

 retired districts of Europe. 



Use of Salt. Among other follies of the 

 day, some indiscreet persons are objecting 

 to the use of salt, and propose to do without 

 it. Nothing could be more absurd. Com- 

 mon salt is the most widely-distributed sub- 

 stance in the body ; it exists in every fluid 

 and in every solid ; and not only is it every- 

 where present, but in almost every part it 

 constitutes the largest portion of the ash 

 when any tissue is burned. In particular, it 

 is a constant constituent of the blood, and 

 it maintains in it a proportion that is almost 

 wholly independent of the quantity that is 

 consumed with the food. The blood will 

 take up so much and no more, however 

 much we may take with our food ; and, on 

 the other hand, if none be given, the blood 

 parts with its natural quantity slowly and un- 

 willingly. Under ordinary circumstances, a 

 healthy man loses daily about twelve grains 

 by one channel or the other, and, if he is to 

 maintain his health, that quantity must be 

 introduced. Common salt is of immense 

 importance in the processes ministering to 



the nutrition of the body, for not only is it 

 the chief salt in the gastric juice, and essen- 

 tial for the formation of bile, and may hence 

 be reasonably regarded as of high value in 

 digestion, but it is an important agent in 

 promoting the processes of diffusion, and 

 therefore of absorption. Direct experiment 

 has shown that it promotes the decomposi- 

 tion of albumen in the body, acting, proba- 

 bly, by increasing the activity of the trans- 

 mission of fluids from cell to cell. Nothing 

 can demonstrate its value better than the 

 fact that, if albumen without salt is intro- 

 duced into the intestine of an animal, no 

 portion of it is absorbed, while it all quickly 

 disappears if salt be added. If any further 

 evidence were required, it would be found 

 in the powerful instinct which impels ani- 

 mals to obtain salt. Buffaloes will travel 

 for miles to reach a " salt-lick " ; and the 

 value of salt in improving the nutrition and 

 the aspect of horses aud cattle is well known 

 to every farmer. The popular notion that 

 the use of salt prevents the development of 

 worms in the intestine has a foundation in 

 fact, for salt is fatal to the small thread- 

 worms, and prevents their reproduction by 

 improving the general tone and the charac- 

 ter of the secretions of the alimentary canal. 

 The conclusion, therefore, is obvious that 

 salt, being wholesome, and indeed necessary, 

 should be taken in moderate quantities, and 

 that abstention from it is likely to be inju- 

 rious. Lancet. 



Intelligence of a Turret-Spider. The 



nest of the Tarentula arenicola, or Ameri- 

 can turret-spider, is a vertical tube, extend- 

 ing twelve or more inches into the ground, 

 and projecting half an inch to an inch above 

 the surface. The projecting portion, or tur- 

 ret, is in the form of a pentagon, more or 

 less regular, and is built up of bits of grass 

 and straw, small twigs, etc., cemented with 

 mud, like a miniature old-fashioned chim- 

 ney. The upper part of the tube has a thin 

 lining of web-silk. A nest was exhibited 

 by Vice-President H. C. McCook, D. D., at a 

 meeting of the Academy of Natural Sciences, 

 of Philadelphia, which, during its journey 

 from Vineland, New Jersey, where it was 

 found, had been plugged at top and bottom 

 with cotton. Upon the arrival of the nest 

 in Philadelphia, the plug guarding the en- 



