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the viscid globules, the prumray matter it employs in spinning, each of the thick- 

 ness of about 1-lOth of an inch.* It takes 140 of these globules to form a single 

 spiral line ; it has 24 circumvolutions to go through, which gives the number of 

 3,S60. We have thus got the average total number of lines between two radii of 

 the circle ; jnultiplying that number by 26, the number of radii which the untiring 

 insect springs, gives the total amount of 87,360 viscid globules before the net is 

 complete. The dimension of the net, of course, varies with the species. Some 

 will be composed of as many as 120,000 lines ; yet even to form this net the spider 

 will only take 40 minutes. Wonderful indeed is the process by which the spider 

 draws the thread from its body — more wonderful than any rope or silk spinning. 

 Each of these spinnerets is covered with rows of bristle-like points, so very fine 

 that a space about the size of a pin's head will cover a thousand of them. From 

 each of these points or tubes issues a small but slender thread, which unites with 

 the other threads, forming one compound whole ; these are situated about 1-lOth 

 of an inch from the apex of the sjiinnerets ; they also unite and form one thread, 

 624 of which are used by the spider in forming his net. With the instrument 

 which nature has given him, the claws of his feet, the spider gfuides and arranges 

 the glutinous thread as this seemingly inexhaustible fibre is drawn fron; his body, 

 and interweaves them with each other until the net is complete. In this way 

 spiders are the weavers of a supple line, whose touch, for quickness and fineness, 

 surpasses that of any spinning jenny." 



To get a cast or e-xact copy of a spider's web is not a difficult thing. My 

 plan, as originally undertaken, was to mount a miscroscopical slide of the web 

 itself, and this when dene on slips of larger size than the visual 3 by 1 inch — say 3 

 by 2 inches — is very satisfactory, because it shows the web so very truly. Of course, 

 this way is very advantageous in the case of the garden spider, because when you 

 mount in a cell, you simply suspend the web in air — by this means getting, under 

 the microscope, the correct view as to the thickness of thread, e.xact and relative 

 position and size of gum globules when present, besides other minute pieces of 

 information which could scarcely be obtainable any other way. And, even in this 

 plan, caution is necessary, as also is a steady hand as well as good eyesight, 

 because if you allow the wob to touch the glass of your slide, your web is almost 

 useless. 



But it is not given to everyone to use a microscope, or even if they had one, 

 to be able to get a slide of web to their own satisfaction. Hence, another plan 

 may with fair success be adopted. Get a sheet of paper perfectly flat, a bottle of 

 aniline dye, a spray such as would be used for Eau-de-Cologne or other agreeable 

 scents if you wanted to vaporize a room. Spray the web and, whilst the web is 

 still wet, apply the paper very carefully to the web. The aniline dye on the web 

 leaves its mark on the paper, thus giving an e.xact counterpart of the web, with all 

 its perfections and imperfections. Those of us who live in the country may very 



*This quotation is not very clear. We find that Mr. Blackwall writes as follows : " The 



mean distance between ttuo ritdii'\% 7-ioth of an inch ; if we multiply this number 7 by 20 (the 

 mean number of viscid globules occurring on oiw-teuih of an inch of the spiral line) the product is 

 140, which will be the number of globules on 7-ioth of an inch ; this product, multiplied by 24 

 (the mean number of turns made by the spiral line) give 3,360 as the mean number of globules 

 contained between two radii," &c. — Edit., 1892. 



