Continuity mistake: When the snake with the message "Impostor" written on it twirls around Uncle Monty's wrist, it's perfectly aligned on his wrist - its tail is by Monty's wrist and the head is pointing up his arm. When it cuts, the head is now by the wrist and the tail is pointing up the arm. (00:39:05)
Continuity mistake: After Uncle Morty, Klaus and Violet agrees that Stephano is an impostor and Stephano returns we see him lifting his arm with the hook on up. When it cuts we can see his arm is suddenly lowered. (00:40:50)
Continuity mistake: After the death of Uncle Monty, Stephano says "I do feel somewhat responsible for this tragedy". At the same time you can see a policeman carrying a box passing Violet in the background. When it cuts he passes her again. (00:42:40)
Audio problem: When Count Olaf, dressed as Stephano, runs away and takes off in his car the tires screech. However the road outside Uncle Monty was of dust and sand, not asphalt. (00:45:05)
Continuity mistake: When Mr. Poe is bringing the kids back from Monty, it cuts to a close-up shot inside the car of his hands on each side of the steering wheel. In the next shot his left hand is suddenly on top of the steering wheel. (00:45:20)
Continuity mistake: When Aunt Josephine hands over the photo album to Violet, it is open to a page with a colored picture. As Violet grabs the album, that picture is gone - it's suddenly open on a different page. (00:48:45)
Continuity mistake: When Aunt Josephine hands over the photo album to Violet she hands it over with one hand. When it cuts she is holding it with both hands. (00:48:45)
Continuity mistake: In the scene where the Baudelaires and Aunt Josephine are looking in the photo album, Violet turns a page. You can see the photo Aunt Josephine does not want the orphans to see, but when Violet turns to the next page, the same photo is there. (00:49:10)
Audio problem: When Aunt Josephine says, " Watch the chandelier, if it falls it will impale you." she turns to face the camera about when she says "impale" and her lips aren't moving. (00:50:05)
Continuity mistake: After Aunt Josephine tells how Ike died she starts crying and reaches her arms out at Violet. When it cuts she does the same again. (00:51:15)
Continuity mistake: When Aunt Josephine gives the casket to Klaus and tells them to finish the shopping, one of the handles on the casket falls under the roots of the vegetables while the other handle rests on the roots. Two shots later both handles rest on the roots. (00:55:25)
Continuity mistake: When Hurricane Herman has started to destroy Aunt Josephine's house, the stove's gas pipe disconnects, then we see the rotary wall telephone partly fall from the wall. The handset falls completely off, but in a subsequent shot when the stove is ablaze, the handset is hanging sideways from the phone's cradle. (00:59:45)
Continuity mistake: After the stove disconnects, right before the phone handle is shown fall off, we can see the handle has already fallen off. (00:59:45)
Continuity mistake: When the door handle explodes, Violet and Klaus throw themselves to the floor. When lying on the floor their hands change between shots from being close to each other to far away from each other. (01:00:10)
Continuity mistake: When Klaus sees that they are sitting on a separated piece of Aunt Josephine's house and he says "Violet, you better tie your hair up", the camera zooms out. If you look closely on the broken edge on the house you can see the edge is firm and smooth. But when it cuts from a view from below as they are looking down you can see the edge on the house is full of broken planks. These broken planks weren't there before. (01:00:30)
Continuity mistake: As Violet and Klaus are looking over the edge of the broken house notice the broken planks. In the next shot the planks have changed. Some are shorter, some are longer. Definitely a different stage of scenery. (01:00:45)
Continuity mistake: As Violet sees the anchor you can see a black broken piece of plank hanging to the right of it. When it cuts the plank is gone. (01:00:55)
Continuity mistake: When we first get to see the anchor hanging there is a sack lying next to the closet. Later when they break the support post making the piece of the house they are standing on wiggle, the sack is gone. And it hasn't wiggled enough to send the sack over the edge. (01:00:55 - 01:02:05)
Continuity mistake: As Violet approach the closet where the anchor is hanging she has her right hand up by her waist. When it cuts, it's down. (01:01:05)
Continuity mistake: When Violet tells Klaus to give her the fire extinguisher, it cuts to him saying "Why?" while holding his hand on Sunny's shoulder. When it cuts back to Violet, you can see in the background that his hand is resting down by her arm. (01:01:10)
Chosen answer: The spy glasses are not explained in the books, but it seems that these are symbols of the fact that they are in VFD, the secret organization we learn about later on in the series. Both Dr. Montgomery and Aunt Josephine's husband and brother-in-law, the Anwhistle brothers, are implied to have been a part of VFD.